AP Chemistry - Unit 1 Review

Front

What is ionization energy?

Back

Ionization energy is the energy required to remove an electron from a gaseous atom or ion. It generally increases across a period and decreases down a group in the periodic table.

Front

How do you calculate moles from grams?

Back

To calculate moles from grams, use the formula: Moles = Mass (g) / Molar Mass (g/mol).

Front

What is the percent composition of an element in a compound?

Back

Percent composition is the percentage by mass of each element in a compound, calculated using the formula: (mass of element in 1 mole of compound / molar mass of compound) x 100%.

Front

What is the empirical formula?

Back

The empirical formula is the simplest whole-number ratio of elements in a compound.

Front

How does atomic size affect ionization energy?

Back

As atomic size increases, ionization energy generally decreases because the outer electrons are farther from the nucleus and experience less nuclear attraction.

Front

What is the significance of effective nuclear charge?

Back

Effective nuclear charge is the net positive charge experienced by an electron in a multi-electron atom, influencing ionization energy and atomic size.

Front

What is the molar mass of carbon tetrafluoride (CF4)?

Back

The molar mass of CF4 is calculated as follows: C (12 g/mol) + 4 x F (19 g/mol) = 12 + 76 = 88 g/mol.

Front

How do you determine the empirical formula from percent composition?

Back

Convert the percent composition to grams, then to moles, and find the simplest whole-number ratio of the elements.

Front

What is the trend of ionization energy in the periodic table?

Back

Ionization energy increases across a period (left to right) and decreases down a group (top to bottom).

Front

What is the relationship between moles and molecules?

Back

1 mole of any substance contains Avogadro's number of molecules, which is approximately 6.022 x 10^23.