Chem Mid-Term Practice_INTRO TO CHEM

Front

What are significant figures?

Back

Significant figures are the digits in a number that contribute to its precision. This includes all non-zero digits, any zeros between significant digits, and trailing zeros in the decimal portion.

Front

How many significant figures are in the speed of light, 3.0 x 10^8 m/s?

Back

2 significant figures.

Front

What is a heterogeneous mixture?

Back

A heterogeneous mixture is a mixture in which the components are not uniformly distributed and can be easily separated, such as iron and sand.

Front

What is a chemical change?

Back

A chemical change is a process that involves the transformation of one or more substances into different substances, resulting in a change in energy and the amount of matter.

Front

What is the formula to calculate density?

Back

Density = Mass / Volume.

Front

If calcium chloride has a density of 2.50 g/cm³, what is the volume of 218 g of it?

Back

87.2 cm³.

Front

What is the atomic structure of a neutral atom with 8 protons?

Back

It contains 8 electrons and typically 9 neutrons.

Front

What is the difference between a compound and a mixture?

Back

A compound is a substance formed when two or more elements chemically bond together, while a mixture is a combination of two or more substances that retain their individual properties.

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction.

Front

What is a solution?

Back

A solution is a homogeneous mixture where one substance (the solute) is dissolved in another (the solvent).