Chemistry is the study of matter. What is matter?

• Anything that has mass and takes up space

• A form of energy

• A type of chemical reaction

• A state of equilibrium

Tags

NGSS.MS-PS1-5

What is the difference between precise and accurate?

• Precision refers to how close measurements are to each other, while accuracy refers to how close measurements are to the true value.

• Precision and accuracy both refer to how close measurements are to the true value.

• Precision refers to how close measurements are to the true value, while accuracy refers to how close measurements are to each other.

• Precision and accuracy both refer to how close measurements are to each other.

What is the difference between a qualitative and quantitative observation?

• Qualitative observations are descriptive and involve characteristics that cannot be counted, while quantitative observations are numerical and can be measured.

• Qualitative observations are numerical and can be measured, while quantitative observations are descriptive and involve characteristics that cannot be counted.

• Both qualitative and quantitative observations are numerical and can be measured.

• Both qualitative and quantitative observations are descriptive and involve characteristics that cannot be counted.

How are physical changes different from chemical changes? Give an example of each.

Tags

NGSS.MS-PS1-4

What is the formula for density?

In an experiment, what is the independent variable?

• The variable that is changed or controlled

• The variable that is measured

• The variable that remains constant

• The variable that is dependent on other variables

Tags

NGSS.MS-PS3-4

In an experiment, what is the dependent variable?

• The variable that is changed or controlled

• The variable that is measured

• The variable that remains constant

• The variable that is not used

Tags

NGSS.MS-PS3-4

In an experiment, what is the controlled variable?

• The variable that is changed or manipulated

• The variable that is measured

• The variable that is kept constant

• The variable that is dependent on other variables

How are these numbers written in scientific notation? Circle the largest number.

• 0.000003 = 3.0 x 10^-6

• 0.0000000003 = 3.0 x 10^-10

Use your calculator to solve 3.0 x 10^8 / 6.25 x 10^-7. Use parentheses and the EE button on your calculator.