Any given experiment has numerous control variables, and it's important for a scientist to try to hold all variables constant except for the independent variable. If a control variable changes during an experiment, it may invalidate the correlation between the dependent and independent variables.
It’s copied and pasted from google so make sure to put it in your words :)
Answer:
C. Particle size
Explanation:
The sand, which has smaller particles, will go through the sieve, while the rice (with a larger particle size) will not
<u>Answer:</u> The concentration of unknown phosphoric acid solution is 0.034 M
<u>Explanation:</u>
To calculate the concentration of acid, we use the equation given by neutralization reaction:
where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is NaOH.
We are given:
Putting values in above equation, we get:
Hence, the concentration of unknown phosphoric acid solution is 0.034 M
Answer:
B
Explanation:
Iodine has a negative charge, so it will gain electrons.
