For a closed system, you need two things:
1) a conservation of mass within the boundaries of the system
2) the ability to freely exchange energy to & from the "closed" system with a surrounding external system
So, the answer is <u><em>never</em></u>, since your defining the "system" as the water within the bathtub, and an open bathtub is exposed to evaporation, which is not conserving mass within the defined "system".
Answer:
8.909*10^-4 moles
Explanation:
The mixture contains MgCl
and NaCl with a total mass of 0.4015 g. The mass of precipitate AgCl(aq) is 1.032 g and it has a molar mass of 143.32 g/mol. Therefore, the moles of the precipitate is:
n = 1.032/143.32 = 7.2007*10^-3 moles
Molar mass of NaCl = 58.44 g/mol and the molar mass of MgCl
is 95.21 g/mol. Let the mass (g) of MgCl
in the original mixture be 'x'. Thus:
7.2007*10^-3 = (0.4015-x)/58.44 + 2x/95.21
(7.2007*10^-3)*58.44*95.21 = 95.21(0.4015-x) + 2x(58.44)
40.06505 = 38.227 -95.21x + 116.88x
40.06505 - 38.227 = -95.21x + 116.88x
1.83805 = 21.67x
x = 1.83805/21.67 = 0.0848 g
moles of MgCl
= 0.0848g/95.21 g/mol = 8.909*10^-4 moles
Answer:
Acid is a molecule capable of donating hydrogen ion and they form aqueous solutions with a sour taste while base is a substance that accepts proton from proton donor and in aqueous solution, they have an astringent or bitter taste. Moreover, a good example for base is sodium hydrogen carbonate as baking soda or baking powder and for acid, the most common example is the acetic acid or vinegar.
Answer: 
Explanation:
According to Bronsted and Lowry an acid is a proton donor and base is a proton acceptor.
Therefore, the equation for the reaction will be as follows.

Here,
acts as a base as it is accepting a proton and
acts as an acid because it is donating a proton.