First we have to find moles of C:
Molar mass of CO2:
12*1+16*2 = 44g/mol
(18.8 g CO2) / (44.00964 g CO2/mol) x (1 mol C/ 1 mol CO2) =0.427 mol C
Molar mass of H2O:
2*1+16 = 18g/mol
As there is 2 moles of H in H2O,
So,
<span>(6.75 g H2O) / (18.01532 g H2O/mol) x (2 mol H / 1 mol H2O) = 0.74mol H </span>
<span>Divide both number of moles by the smaller number of moles: </span>
<span>As Smaaler no moles is 0.427:
So,
Dividing both number os moles by 0.427 :
(0.427 mol C) / 0.427 = 1.000 </span>
<span>(0.74 mol H) / 0.427 = 1.733 </span>
<span>To achieve integer coefficients, multiply by 2, then round to the nearest whole numbers to find the empirical formula:
C = 1 * 2 = 2
H = 1.733 * 2 =3.466
So , the empirical formula is C2H3</span>
Answer : The correct option is, 
Explanation :
To calculate the pressure of gas we are using ideal gas equation as:

where,
P = pressure of gas = ?
V = volume of gas = 0.046 L
n = number of moles of gas = 3.4
R = gas constant = 8.314 L.kPa/mol.K
T = temperature of gas = 298 K
Now put all the given values in the above formula, we get:


Therefore, the pressure of gas is, 
The protons come from water. Sulfur oxides dissolve in water to form sulfurous and sulfuric acids, and nitrogen oxides dissolve to form nitrous and nitric acids.
Yes, the chemical reaction occurs because new substance is formed and heat energy is released.
<h3>
What is chemical reaction?</h3>
Chemical reaction is a process in which one or more substances i.e. the reactants, are converted to one or more different substances i.e. the products so we can conclude that the chemical reaction occurs because new substance is formed and heat energy is released.
Learn more about chemical reaction here: brainly.com/question/11231920