The scientific investigation performed by Elaina is missing control variables.
An ideal scientific investigation should vary only the factor, which is examined, like the volume of the music, while all the other factors should be kept constant.
She hasn't controlled for volume, the volume of the music may influence the rate at which the heart rate of the listener will elevate, in the case, and she should have determined the pulse rate of each individual after the similar rate of listening.
She hasn't controlled for age, as an older person would have reacted to loud music differently from a teenager, that is, all her subjects should be of about the similar age group.
She hasn't controlled for wakefulness, that is, each individual would react to music distinctly when asleep and when is awake.
Answer:
in 2.5 mole SO42 there are 25 Eq
A reaction that is spontaneous will always happen. Option D is right.
Explanation:
When certain conditions for reactions are fulfilled the reaction that occurs without any outside intervention with the formation of product is called as spontaneous reaction.
In spontaneous reaction the product is of lesser energy than reactants.
The spontaneous reaction leads to increase in entropy. If the entropy of the system and surrounding is positive the reaction is spontaneous.
During phase change as solid to liquid causes molecules to be disordered and increase in the movement causes increase disorder hence increase in entropy and a spontaneous reaction.
In chemical reactions if on mixing the substances heat is released thus entropy increases. The spontaneous reaction can also occur even if entropy decreases.
The reaction is not spontaneous if Gibb's free energy is negative.
a cell wall, a large centralvacuole<span>, and </span>plastids<span> such as</span>chloroplasts<span>.</span>
Answer:
The observation, identification, description, experimental investigation, and theoretical explanation of natural phenomena