Data:
weight of water before heating = 0.349
weight of hydrate before heateing = 2.107
Formula:
Weight percent of water = [ (weight of water) / (weight of the hydrate) ] * 100
Solution:
Weight percent of water = [ 0.349 / 2.107] * 100 ≈ 16.6 %
Answer: 16.6%
Flammability
Hope it helps!
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:
The particles must be in the correct orientation upon impact.
The particles must collide with enough energy to meet the activation energy of the reaction.
Explanation:
This a problem related to chemical kinetics. The collision theory is one of the theories of reaction rates and it perfectly explains how the effectiveness of colliding molecules dictates the pace of a reaction.
For reactions to occur, there must be collisions between reacting particles. It implies that the collision per unit time and how successful collisions are determines the rate of chemical reactions in most cases. Therefore, for a collision to be successful, colliding particle must have enough energy which is greater than the activation energy of the reaction. In order to also produce the desired products, the colliding particles must be properly oriented.
Answer: Option (D) is the correct answer.
Explanation:
A polymer is a large molecule which contains repeating units.
A polymer forms long chain of atoms which are not necessarily arranged in a ring structure. There are not only double bonds between all the carbon atoms, as there can be single bonds or triple bonds between the atoms of a polymer.
A polymer does not contain many different type of molecules as there are many repeating units and not many molecules in a polymer.
A polymer is made of large molecules with repeating units.
Thus, we can conclude that option (D) is the correct answer.
