Catalyst can speed up chemical reaction without being used up or involved in thr reaction..
The Boyle-Mariotte's law or Boyle's law is one of the laws of gases that <u>relates the volume (V) and pressure (P) of a certain amount of gas maintained at constant temperature</u>, as follows:
PV = k
where k is a constant.
We can relate the state of a gas at a specific pressure and volume to another state in which the same gas is at different P and V since the product of both variables is equal to a constant, according to the Boyle's law, which will be the same regardless of the state of the gas. In this way,
P₁V₁ = P₂V₂
Where P₁ and V₁ is the pressure and volume of the gas to a state 1 and P₂ and V₂ is the pressure and volume of the same gas in a state 2.
In this case, in the state 1 the gas occupies a volume V₁ = 100 mL at a pressure of P₁ = 150 kPa. Then, in the state 2 the gas occupies a volume V₂ (that we must calculate through the boyle's law) at a pressure of P₂ = 200 kPa. Substituting these values in the previous equation and clearing V₂, we have,
P₁V₁ = P₂V₂ → V₂ =
→ V₂ = 
→ V₂ = 75 mL
Then, the volume occupied by the gas at 200 kPa is V₂ = 75 mL
Cytotoxic is a characteristic of a medicine that bears the ability to cure cancer. The timing of the medication is very important because if not used properly, the substance or the drug may damage also even the healthy cells. Thus, it is just right to caution everyone, especially those who are involved, with the right usage of the drug.
First, isotopes <u>are the atoms of a single element whose nuclei have a different number of neutrons</u>, and therefore, differ in mass numbers. You should know that atoms are formed by a nucleus that has a small size and is made up of protons and neutrons. The nucleus is surrounded by a cloud of electrons, which are found in a region of the atom called the cortex.
The mass number, represented as A, <u>is the sum of the number of protons and neutrons in the nucleus</u>. On the other hand, the atomic number (Z) is <u>the number of protons that exist in the nucleus.
</u>
The isotopes of an element X are represented as follows,
<em>(see first attached picture)</em>
It should be noted that the number of neutrons of a chemical element can be calculated as the difference A-Z.
<u>The atomic and mass numbers of bismuth with 125 neutrons are</u>:
Z = 83
A = 83 + 125 = 208
Thus, the atomic symbol of the bismuth isotope with 125 neutrons is:
<em>(see second attached picture)</em>
Option B is correct
K = Kp /Kr
The given equation indicating, the product containing 6 moles of proton whereas the reactant contains 2 mole of bismuth and 3 mole of hydrogen sulphide.
Hence, in reaction B there are 2 mole of bismuth and 3 mole of hydrogen sulphide reacting to produce 6 moles of proton. whereas the concentration of Bi2S3 is not considered as it is present in solid phase.