Solution :
It is given that :
Weight of the antacid tablet = 5.4630 g
4.3620 gram of antacid is crushed and is added to the stomach acid of 200 mL and is reacted.
25 mL of the stomach acid that is partially neutralized required 13.6 mL of NaOH to be titrated for a red end point.
27.7 mL of
solution is equivalent to
of the original stomach acid. Therefore, 13.6 mL of NaOH will take x 
= 12.27 ml of the original stomach acid.
Erica is likely to use reverse osmosis process.it is the method used in the industry to treat water in oil and gas industry .or ultra filtration method is also employed
-101, K=C+273 so in this you would subtract 273 from 172
1.75 moles ChCl3 x (6.02 x 10 ^-23) / 1 mole = 1.0535 x 10^-22 atoms.
hope this was helpful :)
Physical! Because they do not modify the nature of the substance ( if you look at the chemical level) and it is reversible
Vapor is H20
Water is H20
Ice is H20
A chemical changes is not reversible
Burning wood for example! And the reactants interact together to form a new product.