chem 1 3 years old

According to history, the concept that all matter is composed of atoms was first proposed by:

the Greek philosopher Democritus, but not widely accepted until modern times.

Calculate the answer to the correct number of significant figures:

(341.7 - 22.00) + (0.00224 x 814005) =

2.14 x 10^(3)

Multiply 7.2 cm by 3.75 cm by 1.555 cm and round off the answer.

42 cm^(3)

Give the number of significant figures for each of the following numbers:

a) 0.105

b) 6.010

c) 0.0100

d) 8.00 × 10^(2)

Answer 1: 3

Answer 2: 4

Answer 3: 3

Answer 4: 3

Calculate the following to the correct number of significant figures:

3.466 - 0.2342 =

3.232

Consider the numbers 23.68 and 4.12. The sum of these numbers has ____ significant figures, and the product of these numbers has ____ significant figures.

4, 3

*A crucible is known to weigh 24.3162 g. Three students in the class determine the weight of the crucible by repeated weighing on a simple balance. Using the following information, which student has done the most precise determination?

Student A has done the most precise work.

How many of the following numbers have 3 significant figures?

3.003 16.0 0.004 1.24 x 104 0.001204

2

Round the number 89.04997 to three significant figures.

89.0

Perform this multiplication to the correct number of significant figures:

65.2 x 0.0015 x 12.02

1.2

Add 55.5 cm to 0.50 cm and round off the answer.

56.0 cm

Calculate the answer to the correct number of significant figures:

8.71 x 0.0301 / 0.056 =

4.7

Express 55,500,000,000,000,000,000,000 in scientific notation.

5.55 x 10^(22)

Calculate the following to the correct number of significant figures:

212.1 - 89.342 =

122.8

Calculate the following to the correct number of significant figures:

2.301 ÷ 0.0120 =

192

What is the term for the inexactness of an instrumental measurement?

uncertainty

Express 5.55 x 10^(-2) as an ordinary number.

0.0555

0.00555

0.000555

5550

none of the above

What is the term for the digits that exceed the certainty of the instrument?

certain digits

nonsignificant digits

significant digits

uncertain digits

Round off the following measurement to three significant figures: 7268 mL.

7270 mL

Perform this calculation to the correct number of significant figures:

78.222 x (12.02 - 11.52)

39

Which of the following metric rulers has the least uncertainty?

Ruler D, ± 0.05 cm

How do you express 0.0000000000001 in exponential form.

1 × 10^(-13)

Which of the following balances has the least uncertainty?

analytical balance, +/-0.0001 g

How many significant figures are in the number 0.01020?

4

A box measures 3.50 cm x 2.915 cm. What is the proper way to report this area?

10.2 cm^(2)

What is the term for the amount of substance measured by a laboratory balance?

mass

Calculate the following to the correct number of significant figures:

0.023 ÷ 0.123 =

0.19

Which of the following is a basic step in the scientific method?

all of the above

How many significant digits are in the time measurement 0.0036 second?

2

Calculate the answer to the correct number of significant figures:

(3.53 x 0.0840) - (14.8 x 0.046) + 39.011 =

3.9 x 101

38.628

40

38.63

38.6