6.1-6.4 Review

Front

What percent of the atoms in a molecule of ammonia (NH3) are hydrogen?

Back

75% of the atoms in a molecule of ammonia are hydrogen.

Front

How do you estimate 110% of a number without a calculator?

Back

To estimate 110% of a number, multiply the number by 1.1. For example, for $801.50, 110% is approximately $880.

Front

If a rock contains 17.3 grams of quartz and quartz makes up 27.5% of the rock, how do you find the total mass of the rock?

Back

To find the total mass, divide the mass of quartz by its percentage (in decimal form): 17.3 grams / 0.275 = about 62.9 grams.

Front

What is 31% of 60?

Back

31% of 60 is approximately 20.

Front

How do you order fractions and percentages from least to greatest?

Back

Convert all numbers to the same format (fractions or decimals) and compare. For example: 1/5, 26 2/3%, 0.3, 100%.

Front

What is a compound in chemistry?

Back

A compound is a substance formed when two or more elements are chemically bonded together.

Front

What is the formula to calculate percentage?

Back

Percentage = (Part / Whole) x 100.

Front

How do you convert a fraction to a percentage?

Back

To convert a fraction to a percentage, divide the numerator by the denominator and multiply by 100.

Front

What is the relationship between decimals and percentages?

Back

Decimals can be converted to percentages by multiplying by 100. For example, 0.3 = 30%.

Front

What does it mean to estimate a value?

Back

Estimating a value means finding an approximate value that is close to the actual value, often using rounding.