Looters break a statue into pieces. How do you expect the weathering of pieces of rock to change?

Sodium metal reacts with water to produce hydrogen gas and sodium hydroxide according to the chemical equation shown below.

UNO [17]

Answer: The enthalpy change of the reaction is -361.6 kJ

Explanation:

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

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

Moles of sodium = 0.025 moles

Molar mass of sodium = 23 g/mol

Putting values in above equation, we get:

$0.025mol=\frac{\text{Mass of sodium}}{23g/mol}\\\\\text{Mass of sodium}=(0.025mol\times 23g/mol)=0.575g$

We are given:

Mass of water = 100.00 g

Mass of sodium = 0.575 g

Mass of solution = 100.00 + 0.575 = 100.575 g

To calculate the amount of heat absorbed, we use the equation:

$q=m\times C\times \Delta T$

where,

q = amount of heat absorbed = ?

m = mass of solution = 100.575 g

C = specific heat capacity of solution = 4.18 J/g°C

$\Delta T$ = change in temperature = $(T_2-T_1)=(35.75-25.00)=10.75^oC$

Putting all the values in above equation, we get:

$q=100.575g\times 4.18J/g^oC\times 10.75^oC=4519.34J=4.52kJ$

When heat is absorbed by the solution, this means that heat is getting released by the reaction.

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.

For the given chemical reaction:

$2Na(s)+2H_2O(l)\rightarrow NaOH(aq.)+H_2(g)$

When 0.025 moles of sodium is reacted, the heat released by the reaction is 4.52 kJ

So, when 2 moles of sodium will react, the heat released by the reaction will be = $\frac{4.52}{0.025}\times 2=361.6kJ$

Hence, the enthalpy change of the reaction is -361.6 kJ

6 0

3 years ago

Wine goes bad soon after opening because the ethanol (CH,CH,OH) in it reacts with oxygen gas (0.) from the air to form water (11

daser333 [38]

Answer: The mass of water produced is 1.8 grams

Explanation:

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

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

Given mass of ethanol = 4.59 g

Molar mass of ethanol = 46.07 g/mol

Putting values in equation 1, we get:

$\text{Moles of ethanol}=\frac{4.59g}{46.07g/mol}=0.0996mol$

The chemical equation for the reaction of ethanol with oxygen gas follows:

$CH_3CH_2OH+O_2\rightarrow CH_3COOH+H_2O$

By Stoichiometry of the reaction;

1 mole of ethanol produces 1 mole of water.

So, 0.0996 moles of ethanol will produce = $\frac{1}{1}\times 0.0996=0.0996mol$ of water.

Now, calculating the mass of water from equation 1, we get:

Molar mass of water = 18 g/mol

Moles of water = 0.0996 moles

Putting values in equation 1, we get:

$0.0996mol=\frac{\text{Mass of water}}{18g/mol}\\\\\text{Mass of water}=(0.0996mol\times 18g/mol)=1.8g$

Hence, the mass of water produced is 1.8 grams

5 0

2 years ago

How many total atoms are in 0.560 g of P2O5

ioda

Answer:

16.499 × 10∧ 21 atoms

Explanation:

Given data:

mass of P2O5= 0.560 g

number of atoms= ?

first of all we will calculate the molar mass of P2O5:

P = 2×31 g/mol = 62 g/mol

O = 5× 16 = 80 g/mol

molar mass of P2O5 = 142 g/mol

Noe we will find the moles of 0.560 g P2O5:

moles = mass / molar mass

moles = 0.560 g/ 142 g/mol

moles = 0.0039 mol

now we will find the atoms present in 0.0039 moles:

0.0039 × 6.02 × 10∧ 23 molecules

2.357 × 10∧ 21 molecules

P2O5 consist of 7 atoms:

2.357 × 10∧ 21 × 7 = 16.499 × 10∧ 21 atoms

7 0

3 years ago

Aluminum has a specific heat capacity of 0.902 J/g °C. How much energy is released when 1.0 kg

Ghella [55]

Answer:

The energy released is 13.53j

Explanation:

Q = Mc∆temp.

Q = energy

M = mass

c = specific heat capacity

∆temp. = change in temperature

Q = 1 x 0.902 x (35 - 20)

Q = 0.902 x 15 = 13.53j

8 0

3 years ago

PREDICT: Which do you think would be the most adhesive and least adhesive to wax paper and why do you think this?

ICE Princess25 [194]

The answer is B!!!!!

3 0

2 years ago

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