Empiracal And Amounts 2.1 Flashcards
(21 cards)
What is the empirical formula of a compound?
The formula which shows the simplest whole number ratio of atoms of each element in the compound.
What does the molecular formula represent?
The actual numbers of atoms of each element in a molecule
Fill in the blank: The empirical formula shows the _______ number ratio of atoms of each element in a compound.
simplest whole
True or False: The empirical formula can show a more complex ratio than the molecular formula.
False
What is the relationship between empirical and molecular formulas?
The empirical formula represents the simplest ratio, while the molecular formula shows the actual number of atoms.
What is the molar gas volume?
The molar gas volume is the volume of one mole of gas under specified conditions of temperature and pressure, e.g., 24 dm³ at 20 °C (293K) and one atmosphere pressure.
How much volume does 1 mole of any gas occupy at room temperature and pressure?
1 mole of any gas occupies 24 dm³ (24000 cm³) at room temperature and pressure.
How do you calculate the number of moles from the volume of gas?
The number of moles is given by: moles = volume of gas (dm³) / 24.
What does Gay-Lussac’s Law state?
When gases react, the volumes consumed and produced, measured at the same temperature and pressure, are in ratios of small whole numbers.
What is an example of Gay-Lussac’s Law?
Nitrogen gas + 1 dm³ + hydrogen gas → 3 dm³ ammonia gas 2 dm³.
Who proposed Avogadro’s Law?
The Italian chemist Amedeo Avogadro.
What does Avogadro’s Law state?
Equal volumes of gases at the same temperature and pressure contain the same number of molecules.
How can we use Avogadro’s Law in chemical equations?
Whenever we see an equation for a reaction between gases, we can substitute volumes of gases as the same ratio as numbers of molecules.
What is percentage yield?
Percentage yield is the ratio of the actual amount of product obtained to the theoretical amount calculated from the relative formula masses of the reactants, expressed as a percentage.
Why do many chemical reactions not go to completion?
Many chemical reactions do not go to completion because some starting reactants may remain or some product may be lost during isolation.
What is the formula for calculating percentage yield?
The formula for calculating percentage yield is: % Yield = (actual yield / theoretical yield) x 100.
What does percentage yield indicate?
Percentage yield indicates how much product was made compared to how much could possibly have been made after the reaction is completed and products are purified.
What does percentage yield not account for?
Percentage yield does not account for the amount of waste material produced in a reaction.
What is atom economy?
Atom economy is a measure of the mass of reacting material that ends up in the desired product.
Why is atom economy important?
Atom economy is particularly important in industrial processes that often use multi-tonne quantities of reagents.
How is atom economy calculated?
% Atom Economy = (mass of desired products / total mass of products) x 100
