The half life of a radioactive element is the time needed to the element to decay and reach the half amount of the initial amount. Here we have a radioisotope element which decays its half from 10,000 to 5,000 in two days. Therefore, its half life is 2 days.
Here we have to choose the correct statement on the effect of temperature on the motion of the molecules and atoms of a gas.
As the temperature increases the molecules and atoms move faster.
As per the kinetic theory of gas molecules and atoms the kinetic energy (K.E.) of the atom or molecules is related to temperature by the equation
K.E. = 
kT ( k = Boltzmann constant, T = temperature.
Thus as the temperature increases the K.E. increases thus the atom or molecules move faster.
With the decrease of temperature the movement of the atoms or molecules will be less and they will be near to each other.
The increment of temperature increase the K.E. thus the atoms or molecules move apart from each other.
With the decrease of temperature the movement of the atoms or molecules decreases.
Answer: Sugar is very soluble in water. When you add the solid to the tea the key process is that the solid sugar dissolves in the warm liquid: the solid crystals are broken up into molecules which are every dispersed throughout the existing liquid.
Explanation:
It is a completely true statement that a <span>base increases the OH- ion concentration of water. The correct option among the two options that are given in the question is the first option. I hope that this is the answer that you were looking for and the answer has actually come to your desired help.</span>
PH + pOH = 14 ⇒ pOH = 14 - pH
pOH = 14 - 2.5
pOH = 11.5
[H⁺] = 10^(-pH) = 10^(-2.5)
[H⁺] = 0.003 M
[OH⁻] = 10^(-pOH) = 10^(-11.5) = 3 × 10⁻¹² M
[OH⁻] = 3 × 10⁻¹² M
pH = 2.5 implies one significant digit
