Answer: Option (D) is the correct answer.
Explanation:
A chemical reaction is defined as the reaction which causes change in chemical composition of a substance.
According to law of conservation of mass, mass can neither be created nor it can be destroyed. It can only be changed from one form to another.
For example,
Here, total mass of reactants = (1.008 + 35.453) g/mol = 36.461 g/mol
Whereas total mass of products = 36.461 g/mol
This shows that mass remains the same before or after the reaction.
Similarly, the number of atoms of the type involved will remains the same as no change in their nucleus is occurring.
Thus, we can conclude that the following must be the same before and after a chemical reaction.
Answer:
Explanation:
For the simple pendulum problem we need to remember that:
,
where is the angular position, t is time, g is the gravity, and L is the length of the pendulum. We also need to remember that there is a relationship between the angular frequency and the length of the pendulum:
,
where is the angular frequency.
There is also an equation that relates the oscillation period and the angular frequeny:
,
where T is the oscillation period. Now, we can easily solve for L: