Answer:
3.43 %
Explanation:
We need to calculate first the number of moles of CeO2 produced in the combustion. Given its formula we know how many moles of Ce atom are present. From there calculate the mass this number of moles this represent and then one can calculate the percentage.
0.1848 g CeO2 x 1 mol CeO2/172.114g = 0.00107 mol CeO2
0.00107 mol CeO2 x 1 mol Ce/ 1 mol CeO2 = 0.00107 mol Ce
.00107 mol Ce x 140.116 g Ce/ mol = 0.150 g Ce
0.150 g Ce/ 4.3718 g sample x 100 = 3.43 %
Iodine has an electronegativity of 2.5, and potassium has an electronegativity of 0.8, so the difference is:
2.5 - 0.8 = 1.7
Answer:
The molarity is 2M
Explanation:
First , we calculate the weight of 1 mol of NaCl:
Weight 1mol NaCl= Weight Na + Weight Cl= 23 g+ 35, 5 g= 58, 5 g/mol
58,5 g---1 mol NaCl
233,772 g--------x= (233,772 g x1 mol NaCl)/58,5 g= 4 mol NaCl
<em>A solution molar--> moles of solute in 1 L of solution:</em>
2 L-----4 mol NaCl
1L----x0( 1L x4mol NaCl)/4L =2moles NaCl---> 2 M
The correct answer is 42. I know this answer is right because i have already turned my assignment in and got it right.
Answer: Boiling because it makes the molecules in water bounce around.
Hope it helps.