Q: Which of the following is the correct formula for calculating percentage?

$$\dfrac{\text{Part}}{\text{Whole}} \times 100\%$$

Question 1

Which of the following best describes a chemical as defined in chemistry?

Accepted Answer

A substance that has the same composition and properties wherever it is found.

Question 2

A student observes that a metal turns dull when left in air. She proposes that oxygen in the air reacts with the metal. She then places the metal in a sealed container with no air and observes no change. According to the scientific method, what is her proposal that oxygen reacts with the metal called?

Accepted Answer

Hypothesis

Question 3

Which of the following is the correct order of steps in the scientific method?

Accepted Answer

Observation $$\rightarrow$$ Hypothesis $$\rightarrow$$ Experiment $$\rightarrow$$ Conclusion

Question 4

A patient suspects they are allergic to strawberries and decides to avoid them for a week to see if symptoms improve. Which step of the scientific method does this action represent?

Accepted Answer

Experiment

Question 5

What is the value of $$(-8) 	imes 3$$?

Accepted Answer

$$-24$$

Question 6

Which of the following best describes a direct relationship between two variables on a graph?

Accepted Answer

When one variable increases, the other variable also increases.

Question 7

A sample contains $$15\ \mathrm{g} of $$substance A in a total of $$60\ \mathrm{g}. $$What percentage of the sample is substance A?

Accepted Answer

$$25\%$$

Question 8

What is the place value of 4 in the number $$5,421$$?

Accepted Answer

Hundreds

Question 9

Which of the following numbers is correctly written in scientific notation?

Accepted Answer

$$4.5 	imes 10^3$

Question 10

Convert $$0.00052 to $$scientific notation.

Accepted Answer

$$5.2 	imes 10$$^{-4}$$

Question 11

Solve for $$x in $$the equation $$2x + 6 = 14.$$

Accepted Answer

$$x = 4$$

Question 12

Which axis is the vertical axis on a graph?

Accepted Answer

Y-axis

Question 13

A measured number is best described as:

Accepted Answer

A number obtained by measuring something.

Question 14

Which of the following is the correct formula for calculating percentage?

Accepted Answer

$$\dfrac{	ext{Part}}{	ext{Whole}} 	imes 100\%$$

Question 15

Which of the following is an exact number?

Accepted Answer

The number of students in a classroom.

Question 16

What is the result of $$12 - (-5)$$?

Accepted Answer

$$17$$

Question 17

Which of the following best describes significant figures?

Accepted Answer

The digits in a measured number that are used to indicate its precision.

Question 18

A scientist writes the number $$72,000 in $$scientific notation. What is the correct representation?

Accepted Answer

$$7.2 	imes 10^4$

Question 19

Which of the following best describes the coefficient in scientific notation?

Accepted Answer

A number that is at least 1 but less than 10.

Question 20

A student solves $$-7 + 12. $$What is the correct answer and what rule applies?

Accepted Answer

$$5$$, because when adding numbers with different signs, subtract the smaller from the larger and use the sign of the larger value.

GOB Chemistry Chapter 1: Matter, Measurement, and Mathematical Skills

Guida di studio - Domande di pratica

Study guide - Flashcard