Answer:
5 point) Chemists used systems and order because they study the basic unit of all forms of matter, which is the atom . However, there are several different kinds of atoms, called elements . Chemists organize these elements using the periodic table .
Explanation:
Answer:
Force of attraction = 35.96 
N
Explanation:
Given: charge on anion = -2
Charge on cation = +2
Distance = 1 nm = 
m
To calculate: Force of attraction.
Solution: The force of attraction is calculated by using equation,
---(1)
where, q represents the charge and the subscripts 1 and 2 represents cation and anion.
k = 
F = force of attraction
r = distance between ions.
Substituting all the values in the equation (1) the equation becomes
Force of attraction = 35.96 N
Answer:
pH = 4.9
Explanation:
Given data
[H⁺] = 13 × 10⁻⁶ M
The pH is a scale used to determine <em>the acidity or basicity of a solution</em>. The pH is related to the concentration of hydrogen ions through the following expression.
pH = -log [H⁺]
pH = -log 13 × 10⁻⁶
pH = 4.9
Since the pH < 7, the soil is considered to be acid.
B. The sand increases friction by increasing roughness.
This doesn’t have a multiple choice part to answer.
