Answer:
% composition O = 19.9%
% composition Cu = 80.1%
Explanation:
Given data:
Total mass of compound = 3.12 g
Mass of copper = 2.50 g
Mass of oxygen = 3.12 - 2.50 = 0.62 g
% composition = ?
Solution:
Formula:
<em>% composition = ( mass of element/ total mass)×100</em>
% composition Cu = (2.50 g / 3.12 g)×100
% composition Cu = 0.80 ×100
% composition Cu = 80.1%
For oxygen:
<em>% composition = ( mass of element/ total mass)×100</em>
% composition O = (0.62 g / 3.12 g)×100
% composition O = 0.199 ×100
% composition O = 19.9%
Gases
liquids
plasma
solids
condensates <span />
Answer is "0.05 mol".
<em>Explanation;</em>
We can do calculation by using a simple formula as
n = m/M
Where, n is the number of moles of the substance (mol), m is the mass of the substance (g) and M is the molar mass of the substance (g/mol).
Here,
n = ?
m = 2.80 g
M = 56.08 g/mol
By substitution,
n = 2.80 g /56.08 g/mol
n = 0.0499 mol ≈ 0.05 mol
Because flammable objects have certain substances, you know that it is a chemical property. For example, cloth is flammable and has a certain substance that MAKES it flammable. This results in a chemical property.