Answer : The initial volume was, 71.2 mL
Explanation :
To calculate the volume when temperature and pressure has changed, we use the equation given by combined gas law.
The equation follows:

where,
are the initial pressure, volume and temperature of the gas
are the final pressure, volume and temperature of the gas
We are given:
![P_1=0.85atm\\V_1=?\\T_1=66^oC=[66+273]K=339K\\P_2=0.60atm\\V_2=94mL\\T_2=43^oC=[43+273]K=316K](https://tex.z-dn.net/?f=P_1%3D0.85atm%5C%5CV_1%3D%3F%5C%5CT_1%3D66%5EoC%3D%5B66%2B273%5DK%3D339K%5C%5CP_2%3D0.60atm%5C%5CV_2%3D94mL%5C%5CT_2%3D43%5EoC%3D%5B43%2B273%5DK%3D316K)
Now put all the given values in above equation, we get:


Therefore, the initial volume was, 71.2 mL
Pool smell is due, not to chlorine, but to chloramines, chemical compounds that build up in pool water when it is improperly treated. Chloramines result from the combination of two ingredients: (a) chlorine disinfectants and (b) perspiration, oils and urine that enter pools on the bodies of swimmers.
The bonds of a glucose molecule store chemical energy
Answer:
At end point there will a transition from pink to colorless.
Explanation:
As the student put the vinegar in the titrator and NaOH in the beaker, it means that he has poured phenolphthalein in the NaOH solution.
The pH range of phenolphthalein is 8.3-10 (approx), it means it will show pink color in basic medium.
So on addition of phenolphthalein in NaOH the solution will become pink in color.
When we start pouring vinegar from titrator neutralization of NaOH will begin.
On complete neutralization , on addition of single drop of vinegar the solution will become acidic and there will be complete disappearance of pink color solution in the beaker.
The first one is the answer
isotopes of an atom have different number of neutrons . the number of protons are not different in isotopes of an atom