Answer:
- 0.71963 g of Zn
- 0.80256 g of HCl
Step-by-step explanation:
The required mass of reactants can be computed from the number of moles of product.
moles of ZnCl₂ = (1.5 g)/(136.282 g) ≈ 0.0110066 moles
Then the mass of Zn required is ...
mass of Zn = (0.0110066 mol)(65.382 g/mol) = 0.71963 g
Two moles of HCl are used in the reaction with each mole of Zn, so the mass of HCl required is ...
mass of HCl = 2(0.0110066 mol)(36.458 g/mol) = 0.80256 g
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<em>Comment</em>
The discrepancy in the last two decimal places of the weights above versus the calculator output below comes from rounding of moles of Zn to 4 significant digits, instead of 5 or more. The number of moles of ZnCl₂ is closer to 0.0110066.
Answer:
Cost Price = Rs 10000
Step-by-step explanation:
Assume:
Cost of the item = x
Item was sold at a loss of 20%:
Loss = 20% of x = 0.2x
Item sold = x - 0.2x = 0.8x
Item sold at a profit of 10%:
Profit = 10% of x = 0.1x
item sold = x + 0.1x = 1.1x
Solve:
Difference = 1.1x - 0.8x = 0.3x
0.3x = Rs 3000
x = Rs 3000 ÷ 0.3
x = Rs 10000
Answer:
B is the correct chose
Step-by-step explanation:
Use cosine rule,
cos(A)=(b^2+c^2-a^2)/(2bc)
=(10^2+12^2-6^2)/(2*10*12)
=13/15
A=29.926 degrees.................................(A)
cos(B)=(c^2+a^2-b^2)/(2ca)
=(12^2+6^2-10^2)/(2*12*6)
=5/9
B=56.251 degrees.................................(B)
cos(C)=(a^2+b^2-c^2)/(2ab)
=(6^2+10^2-12^2)/(2*6*10)
=-1/15
C=93.823 degrees.................................(C)
Check:29.926+56.251+93.823=180.0 degrees....ok
20 and 45x
We look for a number that can go into both numbers.
5 into 20 is 4 and 5 into 45x is 9x.
5: 20 45x
4 9x
So no other number can go into 4 and 9x again.
So the GCF of 20 and 45x is 5.
Hope this explains it.
