A. if two angles are complementary angles, then the sum of the measures of two angles is 90°.
Answer:
147 ants
Step-by-step explanation:
7 times 3=21 21 times 7= 147
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.
Expand
x^2+3x-10=18
minus 18 both sides
x^2+3x-28=0
find what 2 numbers mutiply to -28 and add to 3
7 and -3
(x+7)(x-3)=0
set each to zero
x+7=0
x=-7
x-3=0
x=3
x=-7 and 3
0.99 is the answer it greater than 0.1