Chemistry Midterm - 2024

Front

The modern periodic table is organized by increasing ________________.

Back

atomic number.

Front

Calculate the average atomic mass of the mixture of the following isotopes: Isotope 1: 55Fe (15% abundance), Isotope 2: 56Fe (85% abundance).

Back

55.90 amu.

Front

____________ two or more atoms combined that can be physically separated.

Back

Mixture.

Front

How could students tell whether a reaction is exothermic?

Back

They could measure the increase in temperature of the mixed substances using a thermometer.

Front

Spoiled milk is an example of a _______________.

Back

Chemical Change.

Front

What is the definition of a mixture?

Back

A combination of two or more substances that can be physically separated.

Front

What is an exothermic reaction?

Back

A reaction that releases heat and increases the temperature of the surroundings.

Front

What is the difference between a chemical change and a physical change?

Back

A chemical change results in the formation of new substances, while a physical change does not.

Front

What is atomic mass?

Back

The weighted average mass of an element's isotopes, measured in atomic mass units (amu).

Front

What does percent abundance refer to in isotopes?

Back

The percentage of a specific isotope present in a naturally occurring sample of an element.