The Math of Chemistry (A to Z)

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What is the ideal gas law?

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The ideal gas law is a fundamental equation in chemistry that relates the pressure (P), volume (V), temperature (T), and number of moles (n) of an ideal gas: PV = nRT, where R is the ideal gas constant.

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How do you convert Celsius to Kelvin?

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To convert Celsius to Kelvin, add 273.15 to the Celsius temperature. For example, 50°C = 50 + 273.15 = 323.15 K.

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What is the empirical formula?

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The empirical formula is the simplest whole-number ratio of atoms of each element in a compound. For example, the empirical formula for hydrogen peroxide (H2O2) is HO.

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What is the molecular formula?

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The molecular formula shows the actual number of atoms of each element in a molecule. For example, the molecular formula for acetylene is C2H2.

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How do you calculate density?

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Density is calculated using the formula: Density = Mass/Volume. For example, if a rock weighs 4.55 kg and has a volume of 2000 mL, its density is 4.55 kg / 2000 mL = 0.002275 kg/mL.

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What is Avogadro's number?

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Avogadro's number is 6.022 x 10^23, which is the number of molecules in one mole of a substance.

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What is a potassium +1 ion?

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A potassium +1 ion (K+) is a potassium atom that has lost one electron, resulting in 19 electrons (the atomic number of potassium is 19).

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What is the difference between mass and weight?

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Mass is the amount of matter in an object, measured in kilograms or grams, while weight is the force exerted by gravity on that mass, measured in newtons.

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What is the significance of the molecular mass?

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Molecular mass is the mass of a molecule, typically expressed in grams per mole (g/mol), and is used to determine the number of moles in a given mass of a substance.

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How do you find the number of molecules in a gas?

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To find the number of molecules in a gas, use the formula: Number of molecules = (Volume in liters x Avogadro's number) / 22.4 L.