Answer:
= 67.79 g
Explanation:
The equation for the reaction is;
4Cr(s)+3O2(g)→2Cr2O3(s)
The mass of O2 is 21.4 g, therefore, we find the number of moles of O2;
moles O2 = 21.4 g / 32 g/mol
=0.669 moles
Using mole ratio, we get the moles of Cr2O3;
moles Cr2O3 = 0.669 x 2/3
=0.446 moles
but molar mass of Cr2O3 is 151.99 g/mol
Hence,
The mass Cr2O3 = 0.446 mol x 151.99 g/mol
<u> = 67.79 g
</u>
The density of a pure gold is 19.32g/cm3
if the volume is 4.30 cm3 then we can calculate the mass using the formula mass=density x volume
mass=19.32*4.30
mass=83.076g
Answer:
X 154
Check solution in explanation
Explanation:
Average atomic mass = ( mass 1× abudance) + ( mass 2× abudance)+ ( mass 3× abudance) / 100
(149×13.8)+(152×44.9) +(154×41.3)/100
2056.2 + 6824.8 + 6360.2/100
=152.412
Answer:
your simpal answer is 177.32
Be= Beryllium= weight 9.01
Cl= Chlorine= weight 35.45
Since there are 2 Chlorine, you have to add Chlorine twice.
9.01 + 35.45 + 35.45= 79.91
Answer: 79.91
(This answer does not include sig.figs)
