All categories

2 years ago

HELP!

Chemistry

1 answer:

katovenus [111]2 years ago

3 0

Answer:

116.88 g

Explanation:

Step 1: Write the balanced equation for the synthesis of NaCl

Na + 1/2 Cl₂ ⇒ NaCl

Step 2: Calculate the moles corresponding to 45.978 g of Na

The molar mass of Na is 22.990 g/mol.

45.978 g × 1 mol/22.990 g = 1.9999 mol

Step 3: Calculate the number of moles of NaCl formed from 1.9999 moles of Na

The molar ratio of Na to NaCl is 1:1. The moles of NaCl formed are 1/1 × 1.9999 mol = 1.9999 mol.

Step 4: Calculate the mass corresponding to 1.9999 moles of NaCl

The molar mass of NaCl is 58.443 g/mol.

1.9999 mol × 58.443 g/mol = 116.88 g

You might be interested in

Using the equations 2 Sr(s) + O₂ (g) → 2 SrO (s) ∆H° = -1184 kJ/mol SrO (s) + CO₂ (g) → SrCO₃ (s) ∆H° = -234 kJ/mol CO₂ (g) → C(

kkurt [141]

<u>Answer:</u> The $\Delta H^o_{rxn}$ for the reaction is 72 kJ.

<u>Explanation:</u>

Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.

According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.

The given chemical reaction follows:

$2SrCO_3(s)\rightarrow 2Sr(s)+2C(s)+3O_2(g)$ $\Delta H^o_{rxn}=?$

The intermediate balanced chemical reaction are:

(1) $2Sr(s)+O_2(g)\rightarrow 2SrO(s)$ $\Delta H_1=-1184kJ$

(2) $SrO(s)+CO_2(g)\rightarrow SrCO_3(s)$ $\Delta H_2=-234kJ$ ( × 2)

(3) $CO_2(g)\rightarrow C(s)+O_2(g)$ $\Delta H_3=394kJ$ ( × 2)

The expression for enthalpy of the reaction follows:

$\Delta H^o_{rxn}=[1\times (\Delta H_1)]+[2\times (-\Delta H_2)]+[2\times (\Delta H_3)]$

Putting values in above equation, we get:

$\Delta H^o_{rxn}=[(1\times (-1184))+(2\times -(-234))+(2\times (394))]=72kJ$

Hence, the $\Delta H^o_{rxn}$ for the reaction is 72 kJ.

4 0

3 years ago

A device that does work with only one movement and changes the size or direction of a force is a(n) ____.

worty [1.4K]

Answer:

A device that does work with only one movement and changes the size or direction of a force is a simple machine.

Explanation:

For applying force, any used basic mechanical devices are simple machines.
Simple machine changes the direction as well as the amplitude of the applied force i.e. we can increase or decrease the magnitude of the force.
A simple machine is the most basic mechanism to use the force as we need in big mechanical machines.
Some of the examples of simple machines are inclined plane, lever, wedge, wheel and axle, pulley, and screw.

6 0

3 years ago

Plzzz help do your best to answer these questions

vovikov84 [41]

The empirical formula is the simplest formula of a chemical compound.

To find the empirical formula, we take the following steps;

Divide the percentage by mass of each element by its relative atomic mass.
Divide the quotient of each by the lowest value obtained instep 1 above
Write the result of step 2 above as the subscript following each atom.

1) O - 88.10/16, H - 11.190/1

O - 5.5, H - 11.19

O - 5.5/5.5, H - 11.19/5.5

O - 1, H - 2

Empirical formula = OH2

2) C - 41.368/12 H - 8.101/1, N - 32.162/14, O - 18.369/16

C - 3, H - 8, N - 2, O - 1

C - 3/1, H - 8/1 N - 2/1 O - 1/1

C - 3, H - 8, N - 2, O - 1

Empirical formula = C3H8N2O

To obtain the molecular formula where n = number of atoms of each element;

Molecular weight = 174.204 g/mol

[ 3(12) + 8(1) + 2(14) + 16]n = 174

n= 174/88

n = 2 (to the nearest whole number)

Hence, we have;

[C3H8N2O]2

The molecular formula is C6H16N4O2

3) C - 19.999/12, H - 6.713/1, N - 46.646/14, O - 26.641/16

C - 2, H - 7, N - 3, O - 2

C - 2/2, H - 7/2, N - 3/2, O - 2/2

C - 1, H - 4, N - 2, O - 1

Empirical formula - CH4N2O

brainly.com/question/1363167

5 0

3 years ago

Please help me with this!!?

Natali5045456 [20]

Answer:

The last answer is right they get half of the mothers genes and half of the fathers genes.

3 0

3 years ago

Rationalize the difference in boiling points between the members of the following pairs of substances. Part APart complete HF (2

Mrrafil [7]

Answer:

HF has the higher boiling point because HF molecules are more polar. Part B: CHBr3 molecules possess stronger intermolecular interaction due to higher molar mass than CHCl3

Explanation:

Fluorine is more electronegative than chlorine. This implies that HF is more polar and possess stronger hydrogen bonds than HCl molecules.

In part B, the magnitude of dispersion forces depend on molar mass, the greater the molar mass, the greater the magnitude of dispersion forces between molecules, hence CHBr3 has a greater boiling point than CHCl3

4 0

3 years ago