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3 years ago

Radioactive elements include all those elements whose nuclei contain more than

Chemistry

1 answer:

andrey2020 [161]3 years ago

6 0

Bbgfbsthgbdvdge fr that’s crazy d. Thx

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Conversion of gaseous nitrogen to liquid nitrogen is an

miss Akunina [59]

Answer:

true

Explanation:

you can't change it back, it's chemically changed

8 0

3 years ago

5.11 g of MgSO₄ is placed into 100.0 mL of water. The water's temperature increases by 6.70°C. Calculate ∆H, in kJ/mol, for the

cupoosta [38]

Answer: Thus ∆H, in kJ/mol, for the dissolution of MgSO₄ is -66.7 kJ

Explanation:

To calculate the entalpy, we use the equation:

$q=mc\Delta T$

where,

q = heat absorbed by water = ?

m = mass of water = ${\text {volume of water}}\times {\text {density of water}}=100.0ml\times 1.00g/ml=100.0g$

c = heat capacity of water = 4.186 J/g°C

$\Delta T$ = change in temperature = $6.70^0C$

$q=100.0g\times 4.184J/g^0C\times 6.70^0C=2803.3J=2.8033kJ$

Sign convention of heat:

When heat is absorbed, the sign of heat is taken to be positive and when heat is released, the sign of heat is taken to be negative.

The heat absorbed by water will be equal to heat released by $MgSO_4$

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass = 5.11 g

Molar mass = 120 g/mol

Putting values in above equation, we get:

$\text{Moles of }MgSO_4=\frac{5.11g}{120g/mol}=0.042mol$

0.042 moles of $MgSO_4$ releases = 2.8033 kJ

1 mole of $MgSO_4$ releases = $\frac{2.8033 kJ}{0.042}\times 1=66.7kJ$

Thus ∆H, in kJ/mol, for the dissolution of MgSO₄ is -66.7 kJ

3 0

3 years ago

Rainwater can have a ph as low as 3,meaning that it is very

GREYUIT [131]

Rainwater can have a ph as low as 3, meaning that it is very C. Acidic

3 0

3 years ago

A chemical reaction takes place in which energy is absorbed arrange the characteristics of the reaction in order from start to f

Nostrana [21]

<span>A chemical reaction in which energy is absorbed is known as an endothermic reaction. The characteristics of the reaction in order from start to finish is as follows:

1. Lower energy of reactants
2. Transition state
3. Higher energy of products

This implies that in an endothermic reaction, </span><span>the products are less stable than the reactants.</span>

5 0

3 years ago

1. What is the new volume of a sample of neon if 5.23 L of the gas, which was originally at 214 mmHg, is compressed until the pr

bulgar [2K]

Here are attached photos, I don’t think they ar links, lmk if they don’t work

in the answering section it didn’t show me the full question so I only saw a little of question 5. Hopefully you get the idea of how to identify which equations to use tho! Good luck!

8 0

3 years ago