Question

2022 chemistry q1 exam

1. a student fills a 100 ml graduated cylinder with water, as shown in the diagram below.

what is the correct volume measurement?
a. 30.3 ml
b. 34 ml
c. 33 ml
d. 33.0 ml

1. two students, garrison and isabella, determined the mass of an object on two different balances. the accepted mass of the object was 2.355 g.

garrison obtained values of 2.531 g, 2.537 g, 2.535 g, and 2.533 g.
isabella obtained values of 2.350 g, 2.404 g, 2.296 g, and 2.370 g.
which statement best describes the results that were obtained by garrison and isabella?
a. isabella and garrison obtained the same accuracy.
b. garrison obtained the better accuracy.
c. garrison obtained the better precision.
d. isabella obtained the better precision.

1. a baby, born in a country that uses the metric system, weighs 4.00 kg and measures from head to toe. the conversions between metric and english system are shown.

2.54 cm = 1.00 in
2.20 lbs = 1000 g
16.0 oz = 1.00 lb
what is the babys weight in ounces?
a. 8.80 ounces
b. 29.1 ounces
c. 64.0 ounces
d. 141 ounces

Explanation:

Step1: Read the meniscus for volume

When reading the volume of a liquid in a graduated - cylinder, we read the bottom of the meniscus. The scale on the graduated cylinder has markings every 1 mL. The bottom of the meniscus is at 33.0 mL.

Step2: Analyze accuracy and precision for mass measurements

Accuracy is how close a measurement is to the accepted value. Precision is how close a set of measurements are to each other.
For Garrison: Values are 2.531 g, 2.404 g, 2.296 g, 2.370 g. The values are spread out widely.
For Isabella: Values are 2.350 g, 2.404 g, 2.296 g, 2.370 g. Isabella's values are closer to each other, so Isabella has better precision. Also, Isabella's values are on average closer to the accepted value of 2.355 g, so Isabella has better accuracy.

Step3: Convert baby's weight from kg to ounces

We know that 1 kg = 2.20 lbs and 16.0 oz = 1.00 lb.
First, convert 4.00 kg to lbs: $4.00\ kg\times\frac{2.20\ lb}{1\ kg}=8.80\ lb$.
Then convert lbs to oz: $8.80\ lb\times\frac{16.0\ oz}{1\ lb}=140.8\ oz\approx141\ oz$.

Answer:

1. D. 33.0 mL
2. D. Isabella obtained the better accuracy and precision.
3. D. 141 ounces