Question

Use the conversion factor 1amu=6.66054 x 10^-24 to answer the following questions.. . a) 1.674 x 10^-24 g of neutrons is how many amu?. . b)what is the mass in grams of one lithium atom(lithium has an atomic weight of 6.94 amu). . c)6.492 x 10^-23 g of potassium is how many amu?

Answer 1

(a) The number of amu is 1.008 amu.

(b) The mass of one lithium atom is
`11.5* 10^(-24)g`

(c) The number of amu is 39.09 amu.

Explanation :

As we are given that conversion factor:

`1amu=1.66054* 10^(-24)g`

(a) To calculate the number of amu.

As,
`1.66054* 10^(-24)g` of neutrons = 1 amu

So,
`1.674* 10^(-24)g` of neutrons =
`(1.674* 10^(-24)g)/(1.66054* 10^(-24)g)* 1amu=1.008amu`

Thus, the number of amu is 1.008 amu.

(b) To calculate the mass of one lithium atom.

As, 1 amu of lithium atom =
`1.66054* 10^(-24)g`

So, 6.94 amu of lithium atom =
`6.94* 1.66054* 10^(-24)g=11.5* 10^(-24)g`

Thus, the mass of one lithium atom is
`11.5* 10^(-24)g`

(c) To calculate the number of amu.

As,
`1.66054* 10^(-24)g` of neutrons = 1 amu

So,
`6.492* 10^(-23)g` of neutrons =
`(6.492* 10^(-23)g)/(1.66054* 10^(-24)g)* 1amu=39.09amu`

Thus, the number of amu is 39.09 amu.

Answer 2

a.) The conversion factor is 1 amu =
`1.66054 ^(-24)g`

To know how many amu in
`1.674x10^(-24)g` grams of neutrons:

`1.674x10^(-24)g ( (x (amu) )/( 1.66054x10^(-24) g))`

=1.00811 amu

b.) The mass in grams of one lithium ion which has an atomic weight of 6.94 amu.


`6.94 amu ((6.66054 ^(-24) g)/(1 amu))` =
`4.62241x10 ^(23) g`

c.) How many amu in 6.492x10^-23g potassium?


`6.492x10^(-23)g ( (x (amu) )/( 1.66054x10^(-24)g ))` = 39.0957 amu