HChem 1st Semester Exam Review - 3

Front

How many atoms are present in a 120.g piece of solid calcium?

Back

1.80 x 10^24 atoms Ca

Front

What happens to electrons in excited atoms during a flame test that produces an intense yellow flame in sodium chloride?

Back

Electrons move to lower energy states within the atoms.

Front

What generally increases as the elements in Group 2 of the periodic table are considered in order of increasing atomic number?

Back

Atomic radius.

Front

What is the number of valence electrons in Iodine?

Back

7

Front

What quantity is the same among atoms of the same element?

Back

Atomic number.

Front

Define atomic number.

Back

The number of protons in the nucleus of an atom, which determines the element's identity.

Front

What is the relationship between atomic radius and atomic number in Group 2 elements?

Back

As atomic number increases, atomic radius also increases.

Front

Explain the concept of valence electrons.

Back

Valence electrons are the electrons in the outermost shell of an atom that are involved in chemical bonding.

Front

What is the significance of the flame test in chemistry?

Back

The flame test is used to identify the presence of certain metal ions based on the color of the flame produced.

Front

How does electronegativity change across a period in the periodic table?

Back

Electronegativity generally increases from left to right across a period.