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3 years ago

Which equation correctly shows an endothermic reaction? *

Chemistry

1 answer:

Nady [450]3 years ago

8 0

It’s A because +1500 kJ is before the arrow. it’s in the reactant side. so it is endothermic.

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Fe(s) + CuSO4(aq) <===> Cu(s) + FeSO4(aq)

Ludmilka [50]

Answer : The original concentration of copper (II) sulfate in the sample is, $5.6\times 10^{-1}g/L$

Explanation :

Molar mass of Cu = 63.5 g/mol

First we have to calculate the number of moles of Cu.

Number of moles of Cu = $\frac{\text{Mass of Cu}}{\text{Molar mass of Cu}}=\frac{89\times 10^{-3}g}{63.5g/mol}=1.40\times 10^{-3}mole$

Now we have to calculate the number of moles of $CuSO_4$

Number of moles of Cu = Number of moles of $CuSO_4$

Number of moles of $CuSO_4$ = $1.40\times 10^{-3}mole$

Now we have to calculate the molarity of $CuSO_4$

$\text{Molarity}=\frac{\text{Moles of }CuSO_4\times 1000}{\text{Volume of solution (in mL)}}$

Now put all the given values in this formula, we get:

$\text{Molarity}=\frac{1.40\times 10^{-3}mole\times 1000}{400.mL}=0.0035M$

To change mol/L into g/L, we need to multiply it with molar mass of $CuSO_4$

Molar mass of $CuSO_4$ = 159.609 g/mL

Concentration in g/L = $0.0035M\times 159.609g/mol=0.5586g/L\approx 5.6\times 10^{-1}g/L$

Thus, the original concentration of copper (II) sulfate in the sample is, $5.6\times 10^{-1}g/L$

3 0

3 years ago

The number of protons plus the number of neutrons in an atom is equal to its

sashaice [31]

Explanation:

mass number....................

7 0

3 years ago

10 grams of sodium hydroxide, NaOH, is dissolved in 0.25 liters of solution. Determine the molarity (M).

lozanna [386]

Answer:

Explanation:

The molarity of a substance is defined as the number of moles of the substance divided by how many liters the solution is. NaOH has a molar mass of about 40 grams, meaning that 10 grams of it would be 0.25 moles. 0.25/0.25= a molarity of 1.

Hope this helps!

3 0

4 years ago

Dribbling a basketball harder into the floor makes it bounce higher is an example of what newton's law?

vodomira [7]

Newton’s third law, because a person(a) is acting upon the ball(b) by dribbling the ball on the floor

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3 years ago

when 0.72 g of a liquid is vaporized at 110° C and 0.967 atm, the gas occupies a volume of 0.559L. The empirical formula of the

Leno4ka [110]

Hydrogen gas mixed with sulfur

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3 years ago