Q. 2.20 - An Introduction to General, Organic, and Biological Chemistry

Question

Identify the exact number(s), if any, in each of the following pair of numbers: 

a. $5$ pizzas and $50.0$ g of cheese

b. $6$ nickels and $16$g of nickel

c. $3$ onions and $3$lb of onions

d. $5$ miles and $5$ cars

Step-by-Step Solution

Answer

Exact number in given pair of numbers is:

a. $5$ pizzas

b. $6$ nickels

c. $3$ onions

d. $5$ cars

Part(a) Step 1: Given information

We need to find out  the exact number(s), if any, in the pair of $5$ pizzas and $50.0$g of cheese.

Part(a) Step 2: Explanation

Measured numbers are the results of measuring a quantity such as our height or a distance and so on. Due to measurement techniques, their values aren't exact.

An exact number is one that can be calculated with absolute accuracy. They can't be simplified or reduced. For instance, $12$ eggs per dozen, $3$ feet in $1$  yard, and so on.

Here, $5$ pizzas is exact number while $50.0$g is a measured quantity.

Part(b) Step 1: Given information

We need to find out  the exact number(s), if any, in the pair of $6$ nickels and $16$ g of nickel.

Part(b) Step 2: Explanation

Measured numbers are the results of measuring a quantity such as our height or a distance and so on. Due to measurement techniques, their values aren't exact.

An exact number is one that can be calculated with absolute accuracy. They can't be simplified or reduced. For instance, $12$ eggs per dozen, $3$ feet in $1$  yard, and so on.

Hence, according to definition, $6$ nickels is exact.

Part(c) Step 1: Given information

We need to find out  the exact number(s), if any, in the pair of $3$ onions and $3$ lb of onions.

Part(c) Step 2: Explanation

Measured numbers are the results of measuring a quantity such as our height or a distance and so on. Due to measurement techniques, their values aren't exact.

An exact number is one that can be calculated with absolute accuracy. They can't be simplified or reduced. For instance, $12$ bananas per dozen, $100$ centimetre in $1$ metre, and so on.

Hence, according  to definition, $3$ onions is exact number.

Part(d) Step 1: Given information

We need to find out  the measured number(s), if any, in the pair of $5$ miles and $5$ cars.

Part(d) Step 2: Explanation

Measured numbers are the results of measuring a quantity such as our height or a distance and so on. Due to measurement techniques, their values aren't exact.

An exact number is one that can be calculated with absolute accuracy. They can't be simplified or reduced. For instance, $12$ bananas per dozen, $100$ centimetre in $1$ metre, and so on.

Hence, according  to definition, $5$ cars is exact number.