Q: Which of the following is the correct formula for converting Celsius to Fahrenheit?

$$F = (C \times \frac{9}{5}) + 32$$

Question 1

Which of the following best explains why graphite and diamond, both made of carbon, have such different properties?

Accepted Answer

The carbon atoms in graphite and diamond are arranged in different structures.

Question 2

A scientist observes that the total mass of materials in a closed container does not change during combustion. Which scientific law does this observation support?

Accepted Answer

Law of conservation of mass

Question 3

Which of the following is an example of a chemical change?

Accepted Answer

Iron rusting in moist air

Question 4

Which statement correctly distinguishes between a scientific law and a scientific theory?

Accepted Answer

A law summarizes a series of related observations; a theory gives the underlying reasons for them.

Question 5

Which of the following is a homogeneous mixture?

Accepted Answer

Sweetened tea

Question 6

A sample of copper is heated from room temperature to $$95^\circ \mathrm{C}. $$What happens to its density?

Accepted Answer

The sample expands.

Question 7

Which of the following is an intensive property?

Accepted Answer

Density

Question 8

A student measures the mass of a lead block four times and gets values close to each other but far from the true value. What type of error is most likely present?

Accepted Answer

Systematic error

Question 9

Which of the following is the correct formula for converting Celsius to Fahrenheit?

Accepted Answer

$$F = (C 	imes \frac{9}{5}) + 32$$

Question 10

Which separation technique would be most appropriate to separate a mixture of sand and water?

Accepted Answer

Filtration

Question 11

A student multiplies $$6.78$$, $$5.903$$, and $$(5.489 - 5.01). $$How many significant figures should the final answer have?

Accepted Answer

2

Question 12

Which of the following is a derived SI unit?

Accepted Answer

Cubic meter

Question 13

Which of the following best describes chemical energy?

Accepted Answer

A type of potential energy

Question 14

A sample contains only one type of atom and cannot be broken down into simpler substances. What is this sample?

Accepted Answer

An element

Question 15

Which of the following is a physical property?

Accepted Answer

Boiling point

Question 16

A solution of salt in water is heated until the water boils away, leaving salt behind. What type of change has occurred?

Accepted Answer

Physical change

Question 17

Which of the following is the correct conversion factor to convert $$1\ \mathrm{in}^2 to$$ $$\mathrm{cm}^2$$?

Accepted Answer

$$(2.54\ \mathrm{cm})^2$ = 1\ \mathrm{in}^2$$

Question 18

Which of the following statements about energy is true according to the law of conservation of energy?

Accepted Answer

Energy is neither created nor destroyed in a physical or chemical change.

Question 19

A student records the following masses for a sample: $$1.01\ \mathrm{g}$$, $$1.02\ \mathrm{g}$$, $$1.00\ \mathrm{g}$$, and $$1.01\ \mathrm{g}. $$The true mass is $$1.50\ \mathrm{g}. $$Which statement best describes the measurements?

Accepted Answer

The measurements are precise but not accurate.

Question 20

Which of the following is an example of a pure substance?

Accepted Answer

Table salt (sodium chloride)

Chapter 1: Matter, Measurements, and Problem Solving – General Chemistry Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard