The answer is D
Hope this helped
Answer:
If you only want to look at concerns then B would be the correct answer because that is a positive when using nuclear energy
Explanation:
Approximately how many atoms of carbon are present in a 120 gram sample of carbon?
A 120-gram sample of carbon contains approximately 6.02 x 10^24 atoms. We calculate this based on the fact that a mole of carbon weighs 12 grams and contains 6.02 x 10^23 atoms.
Explanation:The subject you're studying is related to atoms, more specifically, counting the number of carbon atoms in a given mass. To solve this, we need to understand the concept of a mole. A mole is an amount of substance that contains the same number of entities (atoms in this case) as there are in exactly 12 grams of ¹2C, or carbon-12. Hence, one mole of carbon is equivalent to 12 grams of carbon, and this mole contains 6.02 x 10^23 atoms (this number is called Avogadro's Number).
Given that your sample is 120 grams of carbon, this translates to 10 moles of carbon since 120 grams divided by 12 grams/mole equals 10 moles. So, the number of carbon atoms present in your 120 grams sample would be 10 moles multiplied by Avogadro's number, equating to approximately 6.02 x 10^24 carbon atoms.
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Each substance on the left side of the arrow in a chemical equation is a ____.
Answer:
Each substance on the left side of the arrow in a chemical equation is a reactant.
Explanation:
The chemical changes (chemical reactions) are represented by chemical equations.
The chemical equations show the starting substances and the final substances.
The starting substances of the reaction are the reactants.
A single arrow is used to indicate the direction of the reaction, the reactants are placed on the left side of the equation, and the products appear on the right side.
This sketch shows that:
reactants yield products
general form A + B → C + D
example Na + Cl → NaCl
It is important for people's eyes to remain moist. Describe how your eyes felt after not blinking. Do you think blinking is helpful and protective? Explain.
Yes blinking is helpful, it helps keep the eyes clean and protect them. By blinking you are sweeping away small particles that could be harmful to the eye. Everytime we blink a small quantity of tear comes out wetting the lower third of the cornea
Blinking is essential for keeping the eyes moist and clear of debris, using the lacrimal apparatus to spread tears across the eye's surface, which highlights the importance of blinking for eye protection and comfort.
Blinking is a protective reflex that is crucial for maintaining eye health by keeping the eyes moist and free from debris. When we do not blink, our eyes can start to feel dry and uncomfortable due to the lack of moisture; a condition known as dry eye can occur. The discomfort experienced from not blinking is evidence of the protective role blinking plays.
It is through this reflex that the lacrimal apparatus, comprising the lacrimal gland, lacrimal canaliculi, lacrimal sac, and nasolacrimal duct, produces lacrimal fluid (tears) which hydrates and cleanses the eyes.
The palpebral conjunctiva, the thin membrane lining the eyelids, extends over the sclera (the white of the eye), aiding in the process of distributing the tears across the eye surface. Therefore, blinking is not just helpful but essential for preserving good vision and protecting the eyes from potential irritants and infections.
Which equation represents a neutralization reaction?1) CaO + H2O → Ca(OH)22) 2HCl + Zn → ZnCl2 + H23) H2SO4 + CaCO3→ CaSO4 + H2O + CO24) HNO3 + KOH → KNO3 + H2O
Answer:
4) HNO₃ + KOH → KNO₃ + H₂O.
Explanation:
The neutralization reaction is the reaction between an acid and a base that results in a salt and water.So, the right choice is:
4) HNO₃ + KOH → KNO₃ + H₂O.
Where, an acid (HNO₃) reacts with a base (KOH) and results in a salt (KNO₃) and water.
Green plants use light from the sun to drive photosynthesis. photosynthesis is a chemical reaction in which water (H2O) and carbon dioxide (CO2) chemically react to form the simple sugar glucose (C6H12O6) and oxygen gas (O2). What mass of water is consumed by the reaction of 7.3 g of carbon dioxide?
Answer:
Mass of H₂O is 3.0g
Explanation:
The reaction equation is given as:
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
Parameters that are known:
Mass of CO₂ used = 7.3g
Unknown: mass of water consumed = ?
Solution
To solve this kind of problem, we simply apply some mole concept relationships.
First, we work from the known to the unknown. From the problem, we have 7.3g of CO₂ that was used. We can find the number of moles from this value using the expression below:Number of moles of CO₂ = [tex]\frac{mass}{molar mass}[/tex]
From this number of moles of CO₂, we can use the balanced equation to relate the number of moles of CO₂ to that of H₂O:6 moles of CO₂ reacted with 6 moles of H₂O(1:1)
We can then use the mole relationship with mass to find the unknown.Workings
>>>> Number of moles of CO₂ =?
Molar mass of CO₂ :
Atomic mass of C = 12g
Atomic mass of O = 16g
Molar mass of CO₂ = 12 + (2 x16) = 44gmol⁻¹
Number of moles of CO₂ = [tex]\frac{7.3}{44}[/tex] = 0.166moles
>>>>>> if 6 moles of CO₂ reacted with 6 moles of H₂O, then 0.166moles of CO₂ would produce 0.166moles of H₂O
>>>>>> Mass of water consumed = number of mole of H₂O x molar mass
Mass of H₂0 = 0.166 x ?
Molar mass of H₂O:
Atomic mass of H = 1g
Atomic mass of O = 16
Molar mass of H₂O = (2x1) + 16 = 18gmol⁻¹
Mass of H₂O = 0.166 x 18 = 3.0g
Answer:
The mass of water when it is reacted with [tex]7.3[/tex]g of carbon dioxide is [tex]3[/tex]g.
Explanation:
Given:
Green plants use light from the sun to drive photosynthesis.
sugar glucose:
[tex](C_6H_1_2O_6)[/tex]
oxygen gas:
[tex](O_2)[/tex]
Step 1:
To find the mass of water is consumed by the reaction of [tex]7.3[/tex] g of carbon dioxide
Let,
Mass of water consumed = number of mole of [tex]H_{2} O[/tex] x molar mass
First we have to find molar mass,so
Number of moles of [tex]CO_{2}[/tex][tex]=\frac{mass}{molarmass}[/tex]
Molar mass of [tex]CO_{2}[/tex]Atomic mass = g
Molar mass
= [tex]12 + (2 x16)[/tex]
[tex]=44gmol^{-1}[/tex]
Therefore,Number of moles of
[tex]$\mathrm{CO}_{2}=\frac{7.3}{44}[/tex]
[tex]=0.166 \mathrm}$[/tex]moles
Step 2:
Now we have to find,
Molar mass of [tex]$\mathrm{H}_{2} \mathrm{O}$[/tex]
Atomic mass of [tex]{H\mathrm $}=1 \mathrm{~g}$[/tex]
Atomic mass of [tex]$O=16$[/tex]
Molar mass of
[tex]$\mathrm{H}_{2} \mathrm{O}=(2 \times 1)+16[/tex]
[tex]=18 \mathrm{gmol}^{-1}$[/tex]
Step 3:
Substitute in the formula,
Mass of [tex]H_{2}O[/tex] = [tex]0.166[/tex]x [tex]18[/tex] = [tex]3.0[/tex]g
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What is required for a chemical reaction to occur?
Answer:
In order to a chemical reaction to occur it is necessary that the reactants collide with enough energy and with the right orientation.Explanation:
The conditions for a chemical reaction to occur are explained by the collision theory.
The collision must provide enough energy to overcome the energy barrier called activation energy.
If the energy of the collision is less than the activation energy then the bonds of the reactants will not be broken and the reactants will not be transformed into other substances (products).
Also, to brake the bonds of the reactants and form the new ones of the transition state (intermediate compound known as activated complex), it is needed that the atoms of one molecule hit the right atoms of the other molecule, this is the collision must have the appropriate orientation to yield the products.
A chemist wishes to decrease the vapor pressure of a large volume of water. Which amount of solute will decrease it the most? (Note: Assume each sample of solute completely dissolves in the water.)
A)0.10 mol Al2(SO4)3
B)0.10 mol sucrose
C)0.40 mol glucose
D)0.20 mol NaCl
Answer:c
Explanation:
Answer: A) 0.10 mol [tex]Al_2(SO_4)_3[/tex]
Explanation:
As the relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.
The formula for relative lowering of vapor pressure will be,
[tex]\frac{p^o-p_s}{p^o}=i\times x_2[/tex]
where,
[tex]\frac{p^o-p_s}{p^o}[/tex]= relative lowering in vapor pressure
i = Van'T Hoff factor
[tex]x_2[/tex] = mole fraction of solute
1. For 0.10 mol [tex]Al_2(SO_{4})_3[/tex]
[tex]Al_2(SO_4)_3\rightarrow 2Al^{3+}+3SO_4^{2-}[/tex]
, i= 5 as it is a electrolyte and dissociate to give 5 ions. and concentration of ions will be [tex]2\times 0.1+3\times 0.1=0.5[/tex]
2. For 0.10 mol sucrose
, i= 1 as it is a non electrolyte and does not dissociate, concentration of ions will be [tex]1\times 0.1=0.1[/tex]
3. For 0.40 mol glucose
, i= 1 as it is a non electrolyte and does not dissociate, concentration of ions will be [tex]1\times 0.4=0.4[/tex]
4. For 0.2 [tex]NaCl[/tex]
[tex]NaCl\rightarrow Na^{+}+Cl^{-}[/tex]
, i= 2 as it is a electrolyte and dissociate to give 2 ions, concentration of ions will be [tex]1\times 0.2+1\times 0.2=0.4[/tex]
Thus as concentration of solute is highest for [tex]Al_2(SO_4)_3[/tex] , the vapor pressure will be lowest.
At what stage of a chemical reaction is chemical energy at its highest level?
In any chemical reaction, value of chemical energy is highest at the threshold energy point.
What are chemical reactions?Chemical reactions are those equations in which reactants combine with each other for the formation of the products.
During the process of a chemical reaction, an intermediate complex is formed in which bonds of reactant as well as of products are present and it is most unstable because of high potential energy. This complex is formed at the threshold energy point which is the highest energy level of any chemical reaction.
Hence threshold energy is the highest energy level.
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A neutral atom always contains the same number of
Answer:
A neutral atom always contains the same number of protons and electrons.Explanation:
Neutral means that the net charge is zero.
Atoms have protons, neutrons and electrons.
Neutrons and protons are in the nucleus of the atom. Protons are particles with positive charge and neutrons are particles without charge.
Elctrons, which are surrounding the nucleus, are particles with negative charge.
The relativie charges of protons and electrons are +1 and -1, respectively.
So, in order to have a total net charge of zero, the neutral atom must have the same number of protons as electrons.
The reaction below can be catalyzed by manganese dioxide (MnO2). If you carried out such a reaction, which compound would you expect to find in the reaction container at the end of the reaction?
2H2O2 ?2H2O + O2
A. MnO
B. MnH2
C. MnO2
D. MnOH
Answer:
[tex]\boxed{\text{C. MnO$_{2}$}}[/tex]
Explanation:
2H₂O₂ ⟶ 2H₂O + O₂
A catalyst is a substance that speeds up a reaction but can be recovered unchanged at the end.
Thus, at the end of the reaction I would expect to find H₂O and MnO₂ in the container.
Water is not listed in any of the options, so I will have to choose [tex]\boxed{\text{C. MnO$_{2}$}}[/tex].
A, B, and D are wrong. They are not reactants, products, or catalysts.
What is the place of metalloids in the periodic table?
HELP ASAP PLEASE!!!
I’m organic compounds all carbon atoms must be bonded only to other carbon atoms.
A. True
B. False
The characteristic functional groups of a protein are _____.
Answer:
[tex]\boxed{\text{amide groups}}[/tex]
Explanation:
A protein is a long chain of amino acids linked together by amide groups.
The general structure is
[tex]\rm \left[-NHCHR-\underbrace{\hbox{CO-NH}}_{\hbox{amide group}}-CHRCO-\right]_{n}[/tex]
What characterizes a strong acid or base? complete ionization in water polar covalent bonding presence of a hydroxide or hydrogen ion ionic bonding?
1. Complete ionization in water.
2. Ionization constant.
3. A good hydrogen-ion acceptor.
4. Weak acid.
5. This base ionizes slightly in aqueous.
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The main characteristic of a strong acid or base is that it completely ionizes in water. Option A is correct.
This means that the acid or base will dissociate into its ions when it is dissolved in water. For example, hydrochloric acid (HCl) is a strong acid that completely ionizes in water to form hydrogen ions (H⁺) and chloride ions (Cl⁻).
HCl(aq) → H⁺(aq) + Cl⁻(aq)
The presence of a hydroxide or hydrogen ion is also a characteristic of strong acids and bases, but it is not the only characteristic. For example, ammonia (NH₃) is a base that does not have a hydroxide ion, but it does dissociate into ammonium ions (NH₄⁺) and hydroxide ions (OH⁻) when it is dissolved in water.
NH₃(aq) + H₂O(l) → NH₄⁺(aq) + OH⁻(aq)
Polar covalent bonding is not a characteristic of strong acids or bases. Polar covalent bonding is a type of bonding that occurs between two atoms that have different electronegativities. The more electronegative atom will have a partial negative charge, while the less electronegative atom will have a partial positive charge. Option A is correct.
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Select the atoms that belong to the same element
Answer:Top Right and Bottom Right.
Explanation:
Proton's define an elements Identity
Answer: The atoms which belong to the same element are atom 2 and atom 5.
Explanation:
Elements are identified by their atomic numbers.
Atomic number is defined as the number of protons or number of electrons that are present in an element.
Atomic number = Number of protons = Number of electrons
Two atoms having same number of protons will belong to same element.
From the given image, atom 2 and atom 5 have same number of protons which are 11.
Thus, both the atoms belong to same element.
Hence, the correct answer is atom 2 and atom 5.
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What happens to a glass of sugar solution when sugar is added to it?
A. The number of moles of water increases.
B. The number of moles of water decreases.
C. The molarity of the solution increases.
D. The molarity of the solution decreases.
Answer:
C. The molarity of the solution increases.
The molarity of the solution increases when sugar is added to the solution of water.
What is molarity?Molarity is defined as the amount of a substance present in a specific volume of solution. Molarity is also called the molar concentration of a solution.
So we can conclude that the molarity of the solution increases when sugar is added to the solution of water due to increase in the concentration.
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The measure of a compounds likeliness to gain or lose an electron is its
Answer:
Is its electrification
Explanation:
Electrification is defined as the ability to gain or lose different electrical charges, usually electrons, and occurs when a collision of subatomic particles occurs. There are three ways to electrify: by rubbing, by contact or by induction. It is necessary to take into account that in these three ways of electrification, the principles of charge conservation and the primary electrostatic rule are present.
The human eye is able to detect as little as 2.35 × 10–18 j of green light of wavelength 510 nm. Calculate the minimum number of photons of green light that can be detected by the human eye. Physical constants can be found here.
The minimum number of photons of green light, with 2.35x10⁻¹⁸ J of energy and 510 nm of wavelength, that can be detected by the human eye is 6.04 photons.
The energy of a single photon is given by:
[tex] E_{1} = h\frac{c}{\lambda} [/tex]
Where:
h: is the Planck constant = 6.62x10⁻³⁴ J*s
λ: is the wavelength of the green light = 510 nm = 510x10⁻⁹ m
c: is the speed of light = 3.00x10⁸ m/s
So, the energy of one photon is:
[tex]E_{1} = h\frac{c}{\lambda} = 6.62 \cdot 10^{-34} Js\frac{3.00 \cdot 10^{8} m/s}{510 \cdot 10^{-9} m} = 3.89 \cdot 10^{-19} J[/tex]
Now, since the energy of the green light detected by the human eye is 2.35x10⁻¹⁸ J, the minimum number of photons (n) to produce that amount of energy is:
[tex] E_{n} = nE_{1} [/tex]
[tex] n = \frac{E_{n}}{E_{1}} = \frac{2.35 \cdot 10^{-18} J}{3.89 \cdot 10^{-19} J} = 6.04 [/tex]
Therefore, the minimum number of photons of green light is 6.04 photons.
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s it possible for several scientists who have never met each other to contribute to the same scientific knowledge, theory, or law?
Explain your answer. (4 points)
Answer:
Yes
Explanation:
People in the same scientific field quickly come to know one another because they publish the same sort of articles in journals that are dedicated to their field.
Their experiments and findings are immediately understood by others reading the journal. Its a case of news travels fast, especially when the news is known to everyone.
What characteristics do solid ionic compounds share?
Answer:
Form crystals.HIgh boiling point and melting pointsBad conductors of electricityHigh hardnessExplanation:
Just a brief introduction to remember what the ionic compounds are. Ionic compounds are the compounds formed by ionic bonds, i.e. the eletrostatic attraction between cations (positivie ions) and anions (negative ions). The ionic compounds are mostly either oxides or salts. An example of an ionic oxide is CaO, and an example of an ionic salt is NaCl.
The strength of the ionic bonds is responsible for most of the characteristics of these compounds. These are the most common characteristics that solid ionic compounds share:
They form cristals: the ionic compounds form long networks of atoms very organized, instead of individual units. That is why you must not refer to these compounds as molecules.HIgh boiling and melting points: because high energy is required to separate the ions, and form the new state.Bad conductors of electricity: since the ions are in fixed position, they do not carry charges (the charges are not moving), so in solid state, the ionic compounds are bad conductors (but in aqueous solution they are very good conductors).Hardness: crystals are relatively hard and when they are hammered they brake apart.What is the molar mass of MgCl2? Report your answer to the nearest 0.1 g/mol.
Answer:
95.2 g/mol
Explanation:
To calculate the molar mass of MgCl2
We have to separately see the molar masses of Magnesium and Chlorine
Molar mass of Magnesium: 24.305 g/mol
Molar mass of Chlorine: 35.453 g/mol
As there are two atoms of chlorine in the said molecule so the molar mass of chlorine will be multiplied by 2.
35.453*2 = 70.906 g/mol
So the total molar mass of the said molecule = Molar mass of Mg + Molar mass of two atoms of chlorine
= 24.305 + 70.906
=95.211 g/mol
Rounding off to .1
95.2 g/mol
The molar mass of magnesium chloride (MgCl₂) is calculated by summing the molar mass of magnesium (24.31 g/mol) with twice the molar mass of chlorine (35.45 g/mol for each Cl), resulting in 95.21 g/mol.
The molar mass of magnesium chloride (MgCl₂) can be calculated by adding the molar masses of magnesium (Mg) and chlorine (Cl) in the compound. Magnesium has a molar mass of 24.31 g/mol, and since there are two chlorine atoms in MgCl₂, we must consider the molar mass of Cl (approximately 35.45 g/mol) twice.
Thus, the molar mass of MgCl₂ is calculated as:
24.31 g/mol (for Mg) + 2 * 35.45 g/mol (for Cl) = 95.21 g/mol.
Therefore, the molar mass of MgCl₂ is 95.21 g/mol, which we would report to the nearest 0.1 g/mol as required.
What is added to white sugar to create brown sugar?
Brown sugar is made by adding molasses to refined white sugar, which may have been processed using bone char. The addition of molasses gives the distinct color and flavor to brown sugar.
Brown sugar is created by adding molasses to refined white sugar. This addition not only gives brown sugar its distinct color, but also imparts a rich flavor and increases the moisture content compared to white sugar. In the production process of brown sugar, it is important to note that if the white sugar utilized has been refined using bone char as a decolorizing filter, then the same process would likely be used in the production of the brown sugar from that manufacturer.
Bone char is derived from animal bones, and even though it is widely used in the sugar industry to achieve the white color of sugar, some consumers may seek alternatives due to dietary preferences or ethical concerns.
Sugar comes in various forms including beet sugar, cane sugar, and specialty sugars like coconut sugar or maple sugar. As for icing or powdered sugar, often used in icings and baked goods, it consists of refined sugar mixed with cornstarch and might also involve the use of bone char in its production.
There are several ways to express solution concentration: dilute, concentrated, ppm, molarity, molality, normality. All of these have one thing in common. They describe the A) weight of solute mixed with a specific volume of water. B) quantity of solute dissolved in a given quantity of solvent. C) quantity of solvent dissolved in a given quantity of solute. D) amount in grams of solute dissolved in the volume of solvent.
Answer:
just pick b
Explanation:
Na2O How many atoms of each element are in this compound? A. 2 sodium atoms and 1 oxygen atom B. 2 sodium atoms and 2 oxygen atoms C.1 sodium atoms and 1 oxygen atoms D.1 sodium atom and 2 oxygen atoms
Answer:
A
Explanation:
There are 2 sodium atoms and 1 oxygen atom.
In Na2O, there are 2 sodium atoms and 1 oxygen atom, as indicated by the chemical formula, which represents a 2:1 ratio of sodium to oxygen with an overall neutral charge.
The compound Na2O consists of two elements: sodium (Na) and oxygen (O). According to the chemical formula, for every one unit of this compound, there are two sodium atoms and one oxygen atom. This is because the subscript '2' next to Na in the formula indicates there are two sodium atoms, while the absence of a number next to O implies there is one oxygen atom. Hence, in the compound Na2O, the ratio of sodium to oxygen atoms is 2:1, which is due to the need for the number of electrons lost by sodium (each Na atom loses one electron) to equal the number of electrons gained by oxygen (the O atom gains two electrons) and ensure the compound has an overall neutral charge. Therefore, the correct answer is A: 2 sodium atoms and 1 oxygen atom.
Some properties, like boiling point elevation and freezing point depression, change in solutions due to the presence and number of of solute particles dissolved in the solvent. These properties are called ___________ properties. A) chemical B) colligative C) qualitative D) quantitative
D. quantitative properties
Boiling point and freezing point depression are both values that can be represented quantitatively (in number form).
Answer:
the correct answer is b
Explanation:
i just got it right on usatestprep
Why is liquid mercury a good electrical conductor in terms of atomic structure?
Mercury is a heavy, silvery-white liquid metal. Compared to other metals, it is a poor conductor of heat, but a fair conductor of electricity. ... Because this configuration strongly resists removal of an electron, mercury behaves similarly to noble gases, which form weak bonds and hence melt at low temperatures.
Answer:
Explanation:
On the periodic table, Mercury belongs to group 12 and period eight(8). It has the Atomic number of eighty(80).
PHYSICAL PROPERTIES OF MERCURY:
Mercury is a d-block element and it is a liquid at standard pressure and temperature. It is silvery and heavy. It has boiling point of 629.88 K, Heat of fusion of 2.29 kJ/mol,molar heat capacity of 27.98
J/mol/K.
STRUCTURE:
Mercury is closed pack. The packing of Mercury makes it to conduct electricity better than alkaline earth metals. Mercury has a Rhombohedral crystal structure.
CONCLUSION:
Mercury has a structure which is efficiently packed and this allow its electrons to move freely. The free electrons can easily move to the conduction band.
If 89.6 joules of heat 20.0 grams of iron from 30.0 C to 40.0 C, what is the specific heat of the iron in J/g.C?
Answer:
H = m c ΔT
89.6 J = (20.0 g) × c × (40.0 - 30.0)°C
Specific heat of iron, c = 89.6 / [20.0 × (40.0 - 30.0)] J/(g°C) = 0.448 J/(g°C)
If 89.6 joules of heat 20.0 grams of iron from 30.0 C to 40.0 C, then the specific heat of the iron in J/g. degree C is 0.448 J/g. degree C.
How do we calculate the specific heat?The formula which we used to calculate the amount of specific heat of any substance involved in a chemical reaction is:
Q = mcΔT, where
Q = absorbed heat = 89.6 Jm = mass = 20gc = specific heat = ?ΔT = change in temperature = 40 - 30 = 10 degree COn putting all these values, we get
c = 89.6 / (20)(10) = 0.448 J/g. degree C
Hence, 0.448 J/g. degree C is the specific heat of iron.
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41 g of MgCl^2 is how many moles of magnesium chloride?
Answer:
0.43 mol.
Explanation:
Knowing that the no. of moles can be calculated using the relation:no. of moles (n) = mass/molar mass
mass of MgCl₂ = 41.0 g & molar mass of MgCl₂ = 95.211 g/mol.
∴ n = mass/molar mass = (41.0 g)/(95.211 g/mol) = 0.43 mol.
Can y’all help me solve these three questions on my review packet?
Answer:
12.
Infrared has the lower frequency while visible light has a higher frequency.
13.
As = 33
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p³
K = 19
1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
Sr = 38
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s²
Kr = 36
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶
14. SEE ATTACHED PICTURE
Explanation:
12. The relationship between wavelength and frequency can be seen in the equations:
[tex]F=\dfrac{c}{\lambda}[/tex] and [tex]\lambda=\dfrac{c}{F}[/tex]
Where:
λ = wavelength
F = frequency
c = constant (speed of light)
As you can see that they are indirectly proportional. So as the frequency increases, the wavelength decreases and vis-a-vis.
13. Electronic configuration of an element can be determined using the pattern attached. It determines the electronic structure of an atom. Remember:
s subshell holds 2 electrons
p subshell holds 6 electrons
d subshell holds 10 electrons
f subshell holds 14 electrons
You know when to stop when the number of electrons sum up to the atomic number (which is the number of protons) in a stable atom.
As = 33
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p³ (Stop here because the electrons sum up to 33)
K = 19
1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
Sr = 38
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s²
Kr = 36
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶
14. Lewis Dot symbol represents how many valence electrons an atom has. You can determine the Lewis Dot Structure also based on the electronic configuration of the element by adding up the number of electrons there are in the highest energy level. The energy level is indicated by the numerical coefficient.
S = 16
1s² 2s² 2p⁶ 3s² 3p⁴
Notice that the highest energy level that appears here is 3, so add up the number of electrons.
2 + 4 = 6 (This is how many valence electrons Sulfur (S) has.)
So we draw the symbol of Sulfur and put three dots around it.
C = 6
1s² 2s² 2p²
2 + 2 = 4
Sr = 38
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s²
2 valence electrons (Because there are only 2 electrons in the 5th energy level)
*Fe = 26
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁶
2 valence electrons (Because there are only 2 electrons in the 4th energy level)
Al = 13 1s² 2s² 2p⁶ 3s² 3p¹
2 + 1 = 3
*Note: Fe or Iron is a transition metal. Technically, 3d in this case is a higher energy level. However, when it comes to Lewis dot structure, d and f shells that are not filled are usually omitted, so it will follow the 4s. Generally when putting dots around we follow the sequence of the X element shown in the attached file.
How many moles are in 2.04 × 1024 molecules of h2o?
Answer:
3.4moles
Explanation:
Given parameters:
Number of molecules = 2.04 x 10²⁴
Unknown: Number of moles
Solution
We use the concept of mole to solve this kind of problem.
A mole is the amount of substance that contains Avogadro's number of particle i.e 6.02 x 10²³ molecules
Solving
For elementary particles:
Number of moles = [tex]\frac{number of particles}{6.02 x 10^{23} }[/tex]¹ molecules
Number of moles = [tex]\frac{2.04 x 10^{24} }{6.02 x ^{23} }[/tex]
Number of moles of H₂O = 0.34 x 10¹ = 3.4moles