How many grams of #Cr(NO_3)_2# are in 8.4 mole?

2 Answers
Mar 24, 2016

Answer:

Chromous nitrate, #Cr(NO_3)_2#, has a formula weight of #176.01# #g*mol#

Explanation:

You have an #8.4# #mol# quantity, which has a mass of #8.4*cancel(mol)xx176.01*g*cancel(mol^-1)# #~=# #1.5# #kg#.

Answer:

Hi there!

With #Cr(NO_3)_2#, there is approximately 1460.97 g in 8.3 moles.

Explanation:

To figure this out, note the relationship between mass, molar mass and moles whereby:

n (moles) = mass/molar mass...

or if you're more of a visual oriented learner, I will show the unit conversion/dimensional analysis method! Either will work!

Let's start off with what you're given:

n = 8.3
m (mass in grams) = ?
M (molar mass) = #Cr(NO_3)_2 = (52.00 g/(mol)+)2((14.01 g/(mol))+3(16.00g/(mol)))#

# M = 176.02 g/(mol) #

Now you know n and M, you can find m using the aforementioned expression! Substituting in you get:

# 8.3 = m/(176.02) #

# m = (8.3)(176.02) #

# m = 1460.97 g #

You can also use unit conversion/dimensional analysis whereby:

# 8.3 mol * 176.02 g/(mol) -> # Moles cancel and you're left with:

# 1460.97 g #

Therefore, in 8.3 moles of #Cr(NO_3)_2#, there is approximately 1460.97 g! Hopefully this was helpful! If you have any questions, let me know! :)