Calcium carbonate can undergo a chemical reaction to produc calcium oxide (CaO) and carbon dioxide (CO₂). Which possible masses of calcium oxide and carbon dioxide can form when 400g of calcium carbonate undergoes this chemical reaction?
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1 point
400g CaO and 0g CO₂
224g CaO and 176g CO₂
40g CaO and 10g CO₂
The atomic mass of the element neon (Ne) is 20.180 amu. Which measurement is correct?
1 point
1 gram Ne = 20.180 moles = 1.215×1025 atoms
1 gram Ne = 20.180 moles = 6.022×1023 atoms
1 mole Ne = 20.180 grams = 1.215×1025 atoms
1 mole Ne = 20.180 grams = 6.022×1023 atoms
When reactants of a reaction are known, which fact can always be deduced about the products?
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1 point
the state of the products
the number of atoms in the products
the number of products
the mass of each product
The atomic mass of carbon (C) is 12.01amu and oxygen (O) is 16.00amu. Which molar mass is correct for carbon dioxide (CO₂)?
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1 point
28.01 g/mol
44.01 g/mol
192.16 g/mol
268.01 g/mol
How many moles is in 43g of CO₂?
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1 point
1204 mol
1.54 mol
2.59 x 10²⁵
According to the law of conservation of matter, which statement best describes a balanced chemical equation?
1 point
The number of moles of atoms of each element must be the same in the reactants and in the products.
The total number of moles of atoms must be the same in the reactants and in the products.
The total number of molecules must be the same in the reactants and in the products.
The number of moles of each molecule must be the same in the reactants and in the products.
Nitrogen gas combines with hydrogen gas to produce ammonia (N₂+3H₂⟶Ammonia). Based on the law of conservation of mass, which could be the product of the reaction?
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1 point
NH₂
NH₃
2NH₃
3NH₂
How do you calculate the number of moles from mass?
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1 point
it is the product of moles and molar mass
it is the quotient of mass and molar mass
it is the product of mass and molar mass
it is the quotient of avogadro's number and molar mass
Sugar reacts with oxygen gas to produce carbon dioxide and water (C₆H₁₂O₆ + 6O₂⟶6CO₂+6H₂O). Which ratio of components is correct?
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1 point
For every 12 moles of CO₂ produced, 2 moles of C₆H₁₂O₆ is needed.
For each mole of O₂, 1 mole of C₆H₁₂O₆ is needed.
For every 5 moles of water produced, 6 moles of oxygen is needed.
What is the molar mass of NH₄Cl?
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1 point
53.5 g/mol
50.5 g/mol
497.0 g/mol