Q: A patient is prescribed a medication containing 250 mg of active ingredient in a 500 mg tablet. What is the percentage of active ingredient in the tablet?

$$\frac{250}{500} \times 100\% = 50\%$$

Question 1

Which of the following best describes the main focus of chemistry as a science?

Accepted Answer

The study of substances in terms of their composition, structure, properties, and reactions.

Question 2

A scientist observes that an antacid tablet fizzes when dropped in water. According to the scientific method, what is the next logical step?

Accepted Answer

Propose a hypothesis explaining why the tablet fizzes.

Question 3

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

Accepted Answer

Observations → Hypothesis → Experiments → Conclusion

Question 4

What is the place value of the digit 2 in the number 15.24 grams?

Accepted Answer

Hundredths

Question 5

Which of the following calculations is correct according to the rules for multiplying positive and negative numbers?

Accepted Answer

$$(3) 	imes (-4) = -12$$

Question 6

A patient is prescribed a medication containing 250 mg of active ingredient in a 500 mg tablet. What is the percentage of active ingredient in the tablet?

Accepted Answer

$$\frac{250}{500} 	imes 100\% = 50\%$$

Question 7

Which of the following best describes a direct relationship as shown in a graph of volume versus temperature for a gas?

Accepted Answer

As temperature increases, volume increases.

Question 8

Express the number 0.00052 in scientific notation.

Accepted Answer

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

Question 9

Which of the following is the correct scientific notation for 64,000?

Accepted Answer

$$6.4 	imes 10$$^{4}$$

Question 10

A scientist collects data and finds that the results do not support the hypothesis. According to the scientific method, what should the scientist do next?

Accepted Answer

Modify the hypothesis and conduct new experiments.

Question 11

Which of the following is the correct way to enter $$2.5 	imes 10$$^{-4}$$ on a scientific calculator?

Accepted Answer

2.5 EE -4

Question 12

If you add $$-7$$ and $$+3$$, what is the result?

Accepted Answer

$$-4$$

Question 13

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 14

A balloon has a volume of 24.0 L at 20°C and 30.0 L at 100°C. What is the relationship between volume and temperature for this gas?

Accepted Answer

Direct relationship

Question 15

Which of the following is the correct way to subtract $$-5$$ from $$8$$?

Accepted Answer

$$8 - (-5) = 13$$

Question 16

A sample contains $$1.2 	imes 10^6$ bacteria. What is this number in standard notation?

Accepted Answer

1,200,000

Question 17

Which of the following is NOT a part of the scientific method?

Accepted Answer

Ignoring experimental results

Question 18

A student calculates the percentage of sugar in a 10 g candy as $$\frac{2}{10} 	imes 100\%. $$What is the correct percentage?

Accepted Answer

20\%

Question 19

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

Accepted Answer

$$8.2 	imes 10^2$

Question 20

If a hypothesis is repeatedly supported by experimental data, what does it become?

Accepted Answer

A scientific law or theory

Chemistry in Our Lives: Introduction and Key Math Skills

Guida di studio - Domande di pratica

Study guide - Flashcard