Quiz Chapter 1 - Chemistry103 ( Pharmacgy )

1. 27 °C is equal ___ °k :

300 °k

290 °k

246 °k

327° k

To convert Celsius to Kelvin, you need to add 273. So, to convert 27 °C to Kelvin, you add 273 to get 300 °K.

Explanation

To convert Celsius to Kelvin, you need to add 273. So, to convert 27 °C to Kelvin, you add 273 to get 300 °K.

2. The SI Unit for amount of substance:

Kilogram

Mole

Meter

Amber

The SI unit for amount of substance is mole. The mole is a unit of measurement that represents the amount of a substance. It is defined as the amount of a substance that contains the same number of entities (such as atoms, molecules, or ions) as there are atoms in 12 grams of carbon-12. The mole is widely used in chemistry and is essential for calculating and comparing the amounts of different substances in chemical reactions.

Explanation

The SI unit for amount of substance is mole. The mole is a unit of measurement that represents the amount of a substance. It is defined as the amount of a substance that contains the same number of entities (such as atoms, molecules, or ions) as there are atoms in 12 grams of carbon-12. The mole is widely used in chemistry and is essential for calculating and comparing the amounts of different substances in chemical reactions.

3. Which of the following is the correct decimal power that corresponds to the prefix nano ?

10-2

10-6

10-3

10-9

The prefix nano corresponds to a decimal power of 10-9. The prefix nano is used to denote one billionth of a unit. In scientific notation, this is represented by multiplying the base unit by 10 raised to the power of -9. Therefore, the correct answer is 10-9.

Explanation

The prefix nano corresponds to a decimal power of 10-9. The prefix nano is used to denote one billionth of a unit. In scientific notation, this is represented by multiplying the base unit by 10 raised to the power of -9. Therefore, the correct answer is 10-9.

4. Convert 50 °k to the Fahrenheit scale.

- 223 °F

223 °F

- 378 °F

- 400 °F

To convert Kelvin to Fahrenheit, you can use the formula: F = (K - 273.15) * 9/5 + 32. Plugging in the given value of 50 K, we get: F = (50 - 273.15) * 9/5 + 32 = -378 °F.

Explanation

To convert Kelvin to Fahrenheit, you can use the formula: F = (K - 273.15) * 9/5 + 32. Plugging in the given value of 50 K, we get: F = (50 - 273.15) * 9/5 + 32 = -378 °F.

5. " The closely individual measurement agree with the true or correct value " . Is :

Accuracy

Precision

A+B

None of the above

Accuracy is the correct answer because it refers to how close individual measurements are to the true or correct value. It is a measure of how well the measurements reflect the true value, regardless of how close they are to each other. Precision, on the other hand, refers to how close multiple measurements are to each other, regardless of their closeness to the true value. Therefore, accuracy is the most appropriate term to describe the given statement.

Explanation

Accuracy is the correct answer because it refers to how close individual measurements are to the true or correct value. It is a measure of how well the measurements reflect the true value, regardless of how close they are to each other. Precision, on the other hand, refers to how close multiple measurements are to each other, regardless of their closeness to the true value. Therefore, accuracy is the most appropriate term to describe the given statement.

6. The following measured number 64100 ± 10 can be expressed ( to the correct significant figures) as :

6.41 x 104

6.4 x 104

6.410 x 104

6.4100 x 104

The given measured number, 64100 ± 10, can be expressed to the correct significant figures as 6.410 x 104. This is because the significant figures are determined by the digits that are known with certainty plus one estimated digit. In this case, the digits 6, 4, 1, and 0 are known with certainty, and the digit 0 is estimated. Therefore, the number is expressed as 6.410 x 104, where 6.410 is the number known with certainty and 104 represents the power of 10.

Explanation

The given measured number, 64100 ± 10, can be expressed to the correct significant figures as 6.410 x 104. This is because the significant figures are determined by the digits that are known with certainty plus one estimated digit. In this case, the digits 6, 4, 1, and 0 are known with certainty, and the digit 0 is estimated. Therefore, the number is expressed as 6.410 x 104, where 6.410 is the number known with certainty and 104 represents the power of 10.

7. The answer of this operation ( 19.6 + 7.8 )( 9.672 - 5.24 ) =

121.4

121

122

121.43

The given expression is a multiplication operation of two sets of parentheses. The first set contains the sum of 19.6 and 7.8, which equals 27.4. The second set contains the difference between 9.672 and 5.24, which equals 4.432. Multiplying these two values together gives us 121.4. Therefore, the correct answer is 121.

Explanation

The given expression is a multiplication operation of two sets of parentheses. The first set contains the sum of 19.6 and 7.8, which equals 27.4. The second set contains the difference between 9.672 and 5.24, which equals 4.432. Multiplying these two values together gives us 121.4. Therefore, the correct answer is 121.

8. Convert 2 km/h to m/s ( to the correct significant figures ):

0.56

0.6

0.556

0.5

To convert km/h to m/s, we need to multiply the value by 1000/3600, as there are 1000 meters in a kilometer and 3600 seconds in an hour. When we calculate 2 km/h to m/s, we get 0.5556 m/s. However, since the question asks for the answer to the correct significant figures, we round it to one decimal place, resulting in 0.6 m/s.

Explanation

To convert km/h to m/s, we need to multiply the value by 1000/3600, as there are 1000 meters in a kilometer and 3600 seconds in an hour. When we calculate 2 km/h to m/s, we get 0.5556 m/s. However, since the question asks for the answer to the correct significant figures, we round it to one decimal place, resulting in 0.6 m/s.

9. Round 1467 to three significant figures :

146

147

1470

1460

To round 1467 to three significant figures, we start from the leftmost digit and count three digits, including any zeros. In this case, the leftmost digit is 1, and the next two digits are 4 and 6. Since the digit after 6 is 7, we round up the last digit, which is 6, to the nearest whole number. Therefore, the rounded number is 1470.

Explanation

To round 1467 to three significant figures, we start from the leftmost digit and count three digits, including any zeros. In this case, the leftmost digit is 1, and the next two digits are 4 and 6. Since the digit after 6 is 7, we round up the last digit, which is 6, to the nearest whole number. Therefore, the rounded number is 1470.

10. The density of copper is 3.4 g/cm³ . If a cube of copper weighs 20.4 g . What is the length of the edge of the cube ?

1.7 cm

1.82 cm

2.00 cm

6.00 cm

The density of a substance is defined as the mass of the substance per unit volume. In this question, we are given the density of copper (3.4 g/cm3) and the weight of a cube of copper (20.4 g). To find the length of the edge of the cube, we can use the formula: density = mass/volume. Rearranging the formula to solve for volume, we get: volume = mass/density. Substituting the given values, we have: volume = 20.4 g / 3.4 g/cm3 = 6 cm3. Since the cube has equal length, width, and height, the length of the edge of the cube is the cube root of the volume, which is approximately 1.82 cm.

Explanation

The density of a substance is defined as the mass of the substance per unit volume. In this question, we are given the density of copper (3.4 g/cm3) and the weight of a cube of copper (20.4 g). To find the length of the edge of the cube, we can use the formula: density = mass/volume. Rearranging the formula to solve for volume, we get: volume = mass/density. Substituting the given values, we have: volume = 20.4 g / 3.4 g/cm3 = 6 cm3. Since the cube has equal length, width, and height, the length of the edge of the cube is the cube root of the volume, which is approximately 1.82 cm.