Chemistry Quarter 1 Review

A student conducting an investigation to determine the effect of temperature on the metabolism of yeast. Yeast and sugar are added to water, the gas produced is captured, and its volume is recorded. Which variables should be held constant during this investigation?

• Mass of sugar and water temperature
• Mass of yeast and mass of sugar
• Volume of gas and water temperature
• Volume of gas and mass of yeast

Tags

NGSS.MS-PS1-2

NGSS.MS-ETS1-1

When experimenting with the growth of a plant, a scientist uses three (of the same type of) plants, two different fertilizers, equal light, and equal water. What type of variable is the fertilizer?

• Dependent
• Independent
• Control
• Constant

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

Should experiments be repeated over and over to see if the results are the same each time?

• yes
• no

Tags

NGSS.MS-PS2-2

In an investigation into the uptake of a protein by cells, scientists immersed two cell types in solutions of this protein. The investigation was carried out at two different temperatures and the percentage of the protein taken up by the two cell types was recorded over 10 minutes. The data was presented in a table, as shown above. Which one of the following conclusions is supported by the data?

• The rate of uptake of this protein at 25 °C is not affected by cell type.
• The percentage of this protein taken up by Cell type 1 is not affected by temperature.
• The rate of uptake of this protein by Cell type 2 is faster at 37 °C than at 25 °C.
• If the experiment continued for another 10 minutes, the percentage of this protein taken up by Cell type 1 would increase.

Tags

NGSS.MS-LS1-5

NGSS.MS-LS2-1

What is the general order of the steps of the scientific methods:

• question, experiment, hypothesis, analyze, results, conclusion, communicate results.
• question, hypothesis, experiment, analyze results, conclusion, communicate results
• question, hypothesis, experiment, analyze results, communicate results, conclusion
• all of the above

Kalinda was trying to explain to her friend the difference between a theory and a law in science.  She used the theory of plate tectonics and the law of superposition as examples.  Kalinda explained the difference by using nonscientific language.  Which statement did Kalinda use to correctly describe the difference between a theory and a law in science?

• A theory describes a natural event, while a law explains it.
• A theory explains a natural event, while a law predicts it.
• A theory explains a natural event, while a law describes it.
• A theory predicts a natural event, while a law explains it.

In 1897, Joseph Thomson discovered that atoms contained electrons. He proposed a change in the atomic theory of that time, and the theory was modified because of his discovery. Since Thomson’s discovery, atomic theory has been further modified. What is the best explanation for why scientific theories are modified?

• Theories more than ten years old are usually out of date.

• Scientists want to prove that the work of other scientists is wrong.

• New evidence that supports a change prompts scientists to modify earlier theories.

• So much information is available today that it is harder to focus research and disprove theories.

Tags

NGSS.MS-LS1-6

Scientists create both scientific theories and scientific laws as they make observations and conduct experiments about the natural world. Which of the following statements most accurately compares the difference between scientific theories and scientific laws

• science laws are based on evidence while science theories are not

• science theories involve only biology, while laws involve all types of science

• science theories involve mathematical equations, while science laws are based on observations

• science theories are ideas that explain natural events, while science laws predict what will happen in a natural event.

Sal is studying the solar system. He makes a physical model using different-sized foam balls to represent the planets. Which best describes why a physical model is a useful tool for studying the solar system?

• Solar system models can be used to study a system that is too big to study directly.
• A model of the solar system eliminates the need for scientists to study the solar system directly.
• A model of the solar system provides an exact replica of the actual solar system, so scientists can experience what each planet is like.
• A model of the solar system can provide more data about the solar system than direct observations.

Tags

NGSS.MS-ESS1-2

NGSS.MS-ETS1-4

The theory of Plate Tectonics is the idea that the Earth's crust has many plates that move because of changes in temperature deep below the Earth's surface. It has changed over time. What would cause the theory to change?

• The addition of new empirical evidence.

• It was a bad theory to begin with.

• If the news ran a story about why it should be changed.

• If a famous scientist said it should be changed.

Tags

NGSS.MS-ESS2-3