Answer:
The density of the substance is 3.9 grams per cubic centimeter.
Explanation:
Given mass=27.3 grams
volume=7 cubic centimeter
We need to find the density.
Density of a substance can be calculated by dividing mass of substance by volume of a substance


Hence Density of the substance is
.
Answer:

Explanation:
1. Mass of zinc
The density of zinc is 7.14 g/cm³
D = m/V

2. Volume of aluminium
The density of aluminium is 2.60/cm³.

Answer:
%KCl = 7.05%
%Water = 92.95%
Explanation:
Step 1: Given data
- Mass of KCl (solute): 36 g
- Mass of water (solvent): 475 g
Step 2: Calculate the mass of the solution
The mass of the solution is equal to the sum of the masses of the solute and the solvent.
m = 36 g + 475 g = 511 g
Step 3: Calculate the mass percentage of the solution
We will use the following expression.
%Component = mComponent/mSolution × 100%
%KCl = 36 g/511 g × 100% = 7.05%
%Water = 475 g/511 g × 100% = 92.95%
Answer:

Explanation:
Hello,
In this case, by knowing that the heat due to a change of temperature is given by:

Whereas Q accounts for the heat, m for the mass, Cp the heat capacity and ΔT for the change in temperature. In such a way the required heat results:

Best regards.
Answer:
12.044 × 10²³ atoms of oxygen
Explanation:
Given data:
Number of atoms of oxygen = ?
Moles of oxygen = 2 mol
Solution:
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 of oxygen
2 mole × 6.022 × 10²³ atoms of oxygen / 1 mole
12.044 × 10²³ atoms of oxygen