Answer: 
Explanation:
Heat of reaction or enthalpy change is the energy released or absorbed during the course of the reaction.
It is calculated by subtracting the enthalpy of reactants from the enthalpy of products.
= enthalpy change = ?
= enthalpy of products
= enthalpy of reactants
For the given reaction :
Answer:
- <em>The volume of 14.0 g of nitrogen gas at STP is </em><u><em>11.2 liter.</em></u>
Explanation:
STP stands for standard pressure and temperature.
The International Institute of of Pure and Applied Chemistry, IUPAC changed the definition of standard temperature and pressure (STP) in 1982:
- Before the change, STP was defined as a temperature of 273.15 K and an absolute pressure of exactly 1 atm (101.325 kPa).
- After the change, STP is defined as a temperature of 273.15 K and an absolute pressure of exactly 105 Pa (100 kPa, 1 bar).
Using the ideal gas equation of state, PV = nRT you can calculate the volume of one mole (n = 1) of gas. With the former definition, the volume of a mol of gas at STP, rounded to 3 significant figures, was 22.4 liter. This is classical well known result.
With the later definition, the volume of a mol of gas at STP is 22.7 liter.
I will use the traditional measure of 22.4 liter per mole of gas.
<u>1) Convert 14.0 g of nitrogen gas to number of moles:</u>
- n = mass in grams / molar mass
- Atomic mass of nitrogen: 14.0 g/mol
- Nitrogen gas is a diatomic molecule, so the molar mass of nitrogen gas = molar mass of N₂ = 14.0 × 2 g/mol = 28.0 g/mol
- n = 14.0 g / 28.0 g/mol = 0.500 mol
<u>2) Set a proportion to calculate the volume of nitrogen gas:</u>
- 22.4 liter / mol = x / 0.500 mol
- Solve for x: x = 0.500 mol × 22.4 liter / mol = 11.2 liter.
<u>Conclusion:</u> the volume of 14.0 g of nitrogen gas at STP is 11.2 liter.
Answer:
Identify the "given" information and what the problem is asking you to "find."
Given : Cl2O7
Find: % Composition (% Cl and %O)
List other known quantities.
Mass of Cl in 1 mol Cl2O7 , 2 Cl : 2 x 35.45 g = 70.90 g
Mass of O in 1 mol Cl2O7 , 7 O: 7 x 16.00 g = 112.00 g
Molar mass of Cl2O7 = 182.90 g/mol
Carbon 12 and carbon 14 are two isotopes of the elements carbon.the difference between carbon 12 and carbon 14 is the number r of neutrons in each atom.the number given after the atom name (carbon) indicates the numbers of protons plus neutron is an atom or iron. Atom of both isotopes of carbon contain 6 protons
