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2 years ago

Jane performed the following trials in an experiment.

Chemistry

1 answer:

zhenek [66]2 years ago

6 0

Answer:

d. The heat absorbed in Trial 2 is about 18420 J greater than the heat absorbed in Trial 1 (16740 J).

Explanation:

The amount of heat absorbed by water (Q) can be calculated from the relation:

Q = m.c.ΔT.

where, Q is the amount of heat absorbed by water,

m is the mass of water,

c is the specific heat capacity of water (c = 4.186 J/g °C),

ΔT is the temperature difference (final T - initial T).

For trial 1:

m = 80.0 g, c = 4.18 J/g °C, ΔT = 65.0 °C – 15.0 °C = 50.0 °C

∴ Q = m.c.ΔT = (80.0 g)(4.18 J/g °C)(50.0 °C) = 16740 J.

For trial 2:

m = 80.0 g, c = 4.18 J/g °C, ΔT = 65.0 °C – 10.0 °C = 55.0 °C

∴ Q = m.c.ΔT = (80.0 g)(4.18 J/g °C)(55.0 °C) = 18420 J.

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A, nonpoint souce pollution is "a main problem with water quality."

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What is the limiting reactant for the reaction below given that you start with 10.0 grams of Al (molar mass 26.98 g mol-1) and 1

mezya [45]

Answer:

Explanation:

4 Al + 3 O₂ → 2 Al₂O₃

You need to figure out which one has the smaller mole ratio. Convert both substances from grams to moles.

(10.0 g Al)/(26.98 g/mol) = 0.3706 mol Al

(19.0 g O₂)/(32.00 g/mol) = 0.5938 mol O₂

Now, use the mole ratios of reactant to product to see which substance produces the least amount of product.

(0.3706 mol Al) × (2 mol Al₂O₃/4 mol Al) = 0.1853 mol Al₂O₃

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2 years ago

A 5.024 mg sample of an unknown organic molecule containing carbon, hydrogen, and nitrogen only was burned and yielded 13.90 mg

Dafna1 [17]

Answer:

C8H17N

Explanation:

Mass of the unknown compound = 5.024 mg

Mass of CO2 = 13.90 mg

Mass of H2O = 6.048 mg

Next, we shall determine the mass of carbon, hydrogen and nitrogen present in the compound. This is illustrated below:

For carbon, C:

Molar mass of CO2 = 12 + (2x16) = 44g/mol

Mass of C = 12/44 x 13.90 = 3.791 mg

For hydrogen, H:

Molar mass of H2O = (2x1) + 16 = 18g/mol

Mass of H = 2/18 x 6.048 = 0.672 mg

For nitrogen, N:

Mass N = mass of unknown – (mass of C + mass of H)

Mass of N = 5.024 – (3.791 + 0.672)

Mass of N = 0.561 mg

Now, we can obtain the empirical formula for the compound as follow:

C = 3.791 mg

H = 0.672 mg

N = 0.561 mg

Divide each by their molar mass

C = 3.791 / 12 = 0.316

H = 0.672 / 1 = 0.672

N = 0.561 / 14 = 0.040

Divide by the smallest

C = 0.316 / 0.04 = 8

H = 0.672 / 0.04 = 17

N = 0.040 / 0.04 = 1

Therefore, the empirical formula for the compound is C8H17N

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2 years ago

Electroplating is a way to coat a complex metal object with a very thin (and hence inexpensive) layer of a precious metal, such

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Answer:

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Ag⁺(aq) + 1 e⁻ → Ag(s)

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1 A = 1 C/s
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