Answer:
the energy of the products is less than the energy of the reactants.
Explanation:
the the change is enthalpy is negative, and heat is released to the surroundings.
Answer:
Mass = 17.8 g
Explanation:
Given data:
Number of atoms of Ca = 2.68 × 10²³
Mass in gram = ?
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
2.68 × 10²³ atoms × 1 mole /6.022 × 10²³ atoms
0.445 mol
Mass in gram;
Mass = number of moles × molar mass
Mass = 0.445 mol × 40 g/mol
Mass = 17.8 g
Answer: X is a Solid; Y is a Gas
Explanation:
There are three (3) states of matter. They are: Solid, Liquid and Gases.
Substance X and Y, belong to the states of matter.
A Solid is a substance that retains its SIZE and SHAPE without need of a container (as opposed to a liquid or gas).
Thus, it will most likely be concluded that: substance X is a Solid; while Y is a Gas
Answer:
37.3g
Explanation:
Formula of the compound:
FeCl₃
Number of chloride ions = 4.13 x 10²³ ions
First find the number of moles in this ions;
6.02 x 10²³ ions are contained in 1 mole of a substance
4.13 x 10²³ ions contains = 0.69mole chloride ions
Now;
3 mole of chloride ions are contained in 1 mole of FeCl₃
0.69 mole of chloride ions will contain = 0.23mole of FeCl₃
To find the mass;
Mass of FeCl₃ = number of moles x molar mass
molar mass of FeCl₃ = 55.8 + 3(35.5) = 162.3g/mol
Mass of FeCl₃ = 0.23 x 162.3 = 37.3g