Answer:
A
Explanation:
When you crumble a piece of paper it make a sound plus i just did on apex
Answer:
[Ar] 3d10 4s2 4p4
Explanation:
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p4
The answer is C :
It controls the entry and exit of substances.
Answer:
We need 226 grams of FeS
Explanation:
Step 1: Data given
Mass of FeCl2 = 326 grams
Molar mass FeCl2 = 126.75 g/mol
Step 2: The balanced equation
FeS + 2 HCl → H2S + FeCl2
Step 3: Calculate moles FeCl2
Moles FeCl2 = 326 grams / 126.75 grams
Moles FeCl2 = 2.57 moles
Step 4: Calculate moles FeS needed
For 1 mol H2S and 1 mol FeCl2 produced, we need 1 mol FeS and 2 moles HCl
For 2.57 moles FeCl2 we need 2.57 moles FeS
Step 5: Calculate mass FeS
Mass FeS = 2.57 moles * 87.92 g/mol
Mass FeS = 226 grams FeS
We need 226 grams of FeS
In 5.70 mol of Hafnium there are 34,326