Answer:
13.4mol of Mg
Explanation:
Given parameters:
Mass of magnesium = 321g
Unknown:
Number of moles = ?
Solution:
The number of moles of a substance is given as;
Number of moles =
Molar mass of Mg = 24g/mol
Insert the parameters and solve;
Number of moles =
= 13.4mol of Mg
Answer:
Sex refers to biological differences between males and females. For example, chromosomes (female XX, male XY), reproductive organs (ovaries, testes), hormones (oestrogen, testosterone). Gender refers to the cultural differences expected (by society / culture) of men and women according to their sex.
Explanation:
Answer: 50. 4g
Explanation:
First calculate number of moles of aluminium in 38.8g
Moles = 38.8g/ 26.982mol/g
= 1.44mol
By looking at the balance equation you can see that 4 moles of aluminium produce 2 moles of aluminium oxide.
4 = 2
1.4 = x
Find the value of x
x= (1.4×2)/4= 0.72 mol
0.72 moles of aluminium oxide are produced from 38.8g of aluminium
Now find the mass of aluminium produced.
Mass = moles × molar mass
= 0.72mol × 69.93 mol/g
= 50.4g
Option (a) is correct.
A reducing agent is the one which loses electrons to other substance and an oxidizing agent is one which accepts electrons.
Here, In

, Cr has oxidation number 6+ in the L.H.S of the equation, but on R.H.S its oxidation number is 0 i.e. it Cr has gained electrons such that total charge is 0.
And the oxidation state of Al in the left-hand side of equation is 0 and in right-hand side, it is +6.i.e. it has donated its electrons to Cr.
Hence, Cr is the oxidizing agent and Al is the reducing agent.