Answer:
146.85 g/mol
Explanation:
PV=nRT
n=mass/molar mass
covert from mmhg to atm = 0.184 atm
convert from ml to L= 0.108 L
convert from degree C to K= 456.15 K
convert from mg to g= 0.07796g
then rearrange the formula:
n=PV/RT
=(0.184)(0.108)/(0.08206)(456.15)
n= 5.308*10^(-4)
rearrange the n formula interms of molar mass:
Molar mass= mass/n
=0.07796/(5.308*10^-4)
molar mass= 146.85g/mol
The chemical properties of the elements are usually drastically changed.
Answer:
1.51 × 10²³ molecules
Explanation:
Given data:
Number of moles of water = 0.250 mol
Number of molecules of water = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
1 mole = 6.022 × 10²³ molecules of water
0.250 mol × 6.022 × 10²³ molecules / 1 mol
1.51 × 10²³ molecules
Answer:
42 liters
Explanation:
Let the volume of 2% sulfuric acid required be X while that of 12% sulfuric acid required be Y.
According to the concentration: 0.02X + 0.12Y = 0.05(X + Y).......equation 1
According to the volume: X + Y = 60...............equation 2
Substitute equation 2 into equation 1.
0.02X + 0.12(Y) = 0.05(60)
2X + 12Y = 300
X + 6Y = 150..............................equation 3
From equation 2, Y = 60 -X...................equation 4
Substitute equation 4 into equation 3.
X + 6(60-X) = 150
X + 360 - 6X = 150
-5X = -210
X = 42
Hence, the volume of 2% sulfuric acid required is 42 liters.