Chemical Formulas

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Chemical Formulas
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1. The formula that indicates the total number of
atoms of the elements in a compound is

1. Empirical formula
2. Molecular formula
3. Structural formula
4. Simplest formula

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2. A compound is 26.58 potassium, 38.02 oxygen,
and 35.4 chromium. The empirical formula of the
compound is

1. KCrO7
2. K2CrO7
3. K2Cr2O7
4. KCr2O7

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3. The formula mass of limewater Ca(OH)2, when Ca
40.1, O 16.0, H 1.0 is

1. 74.1
2. 57.1
3. 58.1
4. 72.1

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4. A mole is the amount of substance or the mass
of a substance that contains

1. 6.02 x1023 particles
2. 60.2 x1023 particles
3. 6.02 x1032 particles
4. 60.2 x1032 particles

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5. Which of the following is not a molecular
formula?

1. HC2H3O2
2. CHO
3. NaOH
4. Na2CO3 . 10H2O

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6. One gram of tin metal burns in air to give
1.27 g of tin oxide. What is the formula of the
oxide?

1. SnO
2. Sn2O2
3. SnO2
4. SnO4

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7. A compound with the simplest formula C2H5O has
a molecular mass of 90. The molecular formula for
the compound is

1. C3H6O3
2. C4H10O2
3. C4H14O
4. C5H14O

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8. Ammonia (NH3) and oxygen can be made to react
to form only N2 formed is

1. 1.5
2. 3.0
3. 0.67
4. 2.0

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9. When acetylene (C2H2) burns in air, the
products are CO2 and H2O. Which of the following
is the balanced equation for the reaction?

1. 2C2 H2 5O2 ? 4CO2 2H2O
2. 4C2 H2 3O2 ? 2CO2 3H2O
3. 3C2 H2 4O2 ? 3CO2 2H2O
4. 2C2 H2 2O2 ? 3CO2 4H2O

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10. How many grams of NaClO3 are required to
produce 5.0g of the solid product?

1. 4.10 g
2. 8.2 g
3. 9.1 g
4. 4.55 g