Answer:
Solving by the method of exponential growth.
bacteria = 2
after one hr = 2² = 4
after 2nd hr = 2³ = 8
after 3rd hr = 2⁴ = 16
after 4th hr = 2⁵ = 32
The concept of atomic masses we can find that the correct answer is:
c) 101
The atomic mass or mass number of an element is the sum of its protons plus the neutrons that are in the atomic nucleus, the electrons are not taken into account because they have a mass much lower than the masses of protons and neutrons.
In the table they indicate that there are 46 protons and 55 neutrons, therefore
M = #_ {protons} + #_ {neutrons}
M = 46 +55
M = 101
In conclusion using the concept of atomic masses we find that the correct answer is:
c) 101
Learn more about atomic mass here:
brainly.com/question/1317964
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.
Answer:
Some of the physical changes used by the industrial chemist in order to identify it is by scratching it with other metals in order to find the hardness of it. Trying to deform it in order to find the malleability, and to heat it and measure the temperature in order to find the melting point.
Some of the chemical changes used by the industrial chemist in order to identify it is by inserting it in water to observe that whether it reacts with it or not, if the reaction is violent, then the metal belongs to either group I or group II. The other method is to insert it in acids of distinct strength and to observe its reaction. The metals belonging to the second group react briskly with acids. The other metals react gradually with acids and others are almost inert.
Formula 1!!!!!!!!!!!!!!!!!!!!!!!!!!