@ What is the wavelength of a radio wave having a frequency of 3.75 X 107 Hz?

Sulfur dioxide, SO 2 ( g ) , can react with oxygen to produce sulfur trioxide, SO 3 ( g ) , by the reaction 2 SO 2 ( g ) + O 2 (

aleksley [76]

Answer: The amount of heat produced by the reaction is -21.36 kJ

Explanation:

Enthalpy change is defined as the difference in enthalpies of all the product and the reactants each multiplied with their respective number of moles.

The equation used to calculate enthalpy change is of a reaction is:

$\Delta H^o_{rxn}=\sum [n\times \Delta H_f_{(product)}]-\sum [n\times \Delta H_f_{(reactant)}]$

For the given chemical reaction:

$2SO_2(g)+O_2(g)\rightarrow 2SO_3(g)$

The equation for the enthalpy change of the above reaction is:

$\Delta H_{rxn}=[(2\times \Delta H_f_{(SO_3(g))})]-[(2\times \Delta H_f_{(SO_2(g))})+(1\times \Delta H_f_{(O_2(g))})]$

We are given:

$\Delta H_f_{(SO_2(g))}=-296.8kJ/mol\\\Delta H_f_{(SO_3(g))}=-395.7kJ/mol\\\Delta H_f_{(O_2(g))}=0kJ/mol$

Putting values in above equation, we get:

$\Delta H_{rxn}=[(2\times (-395.7))]-[(2\times (-296.8))+(1\times (0))]\\\\\Delta H_{rxn}=-197.8kJ/mol$

To calculate the number of moles, we use ideal gas equation, which is:

$PV=nRT$

where,

P = pressure of the gas = 1.00 bar

V = Volume of the gas = 2.67 L

n = number of moles of gas = ?

R = Gas constant = $0.0831\text{ L. bar }mol^{-1}K^{-1}$

T = temperature of the mixture = $25^oC=[25+273]K=298K$

Putting values in above equation, we get:

$1.00bar\times 2.67L=n\times 0.0831\text{ L. bar }mol^{-1}K^{-1}\times 298K\\\\n=\frac{1\times 2.67}{0.0831\times 298}=0.108mol$

To calculate the heat released of the reaction, we use the equation:

$\Delta H_{rxn}=\frac{q}{n}$

where,

q = amount of heat released = ?

n = number of moles = 0.108 moles

$\Delta H_{rxn}$ = enthalpy change of the reaction = -197.8 kJ/mol

Putting values in above equation, we get:

$-197.8kJ/mol=\frac{q}{0.108mol}\\\\q=(-197.8kJ/mol\times 0.108mol)=-21.36kJ$

Hence, the amount of heat produced by the reaction is -21.36 kJ

3 0

2 years ago

2.In a titration, 25.00 cm3 of a solution of hydrochloric acid reacted with 18.40 cm3 of sodium hydroxide solution of concentrat

telo118 [61]

Answer:

0.11mol/dm³

Explanation:

The reaction expression is given as:

HCl + NaOH → NaCl + H₂O

Volume of acid = 25cm³ = 0.025dm³

Volume of base = 18.4cm³ = 0.0184dm³

Concentration of base = 0.15mol/dm³

Solution:

The concentration of hydrochloric acid = ?

To solve this problem, let us first find the number of moles of the base;

Number of moles = concentration x volume

Number of moles = 0.15mol/dm³ x 0.0184dm³ = 0.00276mol

From the balanced reaction equation;

1 mole of NaOH will combine with 1 mole of HCl

Therefore, 0.00276mol of the base will combine with 0.00276mol of HCl

So;

Concentration of acid = $\frac{number of moles }{volume}$ = $\frac{ 0.00276}{0.025}$ = 0.11mol/dm³

4 0

2 years ago

O, li, c which electrons experience the greatest effective nuclear charge? express your answer as a chemical formula.

Nataly_w [17]

The effective nuclear charge of an atom = total electrons - inner electrons For O, ENC = 8 - 2 = 6 For Li, ENC = 3 - 2 = 1 For C, ENC = 6 - 2 = 4 The electrons in O experience the greatest effective nuclear charge and that is why O is smaller than C (which is smaller than Li).

5 0

2 years ago

PLEASE HURRY LIMITED TIME

Stolb23 [73]

3rd one sorry if it’s wrong

3 0

1 year ago

How are a carrot, an amoeba, and a bacterium alike?

PilotLPTM [1.2K]

Answer:

They all are made up of cells

8 0

2 years ago