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3 years ago

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A sled is at rest at the top of a slope 2 m high. The sled has a mass of 45 kg. What is the sled’s potential energy? (Formula: P

E = mgh)
90 J
56.8 J
441 J
882 J

2 answers:

11Alexandr11 [23.1K]3 years ago

5 0

Answer:

D

Explanation:

olga_2 [115]3 years ago

4 0

Explanation:

Gravitational potential energy

= mgh = (45kg)(9.81N/kg)(2m) = 882J.

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3 years ago

What is the percent yield of a reaction in which 200. g of phosphorus trichloride reacts with excess water to form 91.0 g of hcl

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Answer is: <span>yield of a reaction is 56,4%.
</span>Chemical reaction: PCl₃ + 3H₂O → 3HCl + H₃PO₃.
m(PCl₃) = 200 g.
m(HCl) = 91,0 g.
n(PCl₃) = m(PCl₃) ÷ M(PCl₃).
n(PCl₃) = 200 g ÷ 137,33 g/mol.
n(PCl₃) = 1,46 mol.
n(HCl) = m(HCl) ÷ M(HCl).
n(HCl) = 91 g ÷ 36,45 g/mol.
n(HCl) = 2,47 mol.
From reaction: n(PCl₃) : n(HCl) = 1 : 3.
n(HCl) = 1,46 mol · 3 = 4,38 mol.
Yield of reaction: 2,47 mol ÷ 4,38 mol · 100% = 56,4%.

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3 years ago

Under certain conditions Argon gas diffuses at a rate of 3.2 cm per second under the same conditions an unknown gas diffuses at

kozerog [31]

Answer:

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Explanation:

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Squaring both sides, we get

$(\frac{r_{2}}{r_{1}})^{2} = \frac{M_{1}}{M_{2}}$

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3 years ago