Here we have to get the height of the column in meter, filled with liquid benzene which exerting pressure of 0.790 atm.
The height of the column will be 0.928 m.
We know the relation between pressure and height of a liquid placed in a column is: pressure (P) = Height (h) × density of the liquid (ρ) × gravitational constant (g).
Here the pressure (P) is 0.790 atm,
or [0.790 × (1.013 × 10⁶)] dyne/cm². [As 1 atm is equivalent to 1.013 × 10⁶ dyne/cm²]
Or, 8.002ₓ10⁵ dyne/cm².
density of benzene is given 0.879 g/cm³.
And gravitational constant (g) is 980 cm/sec².
On plugging the values we get:
8.002×10⁵ = h × 0.879 × 980
Or, h = 928.931 cm
Or, h = 9.28 m (As 1 m = 100 cm)
Thus the height will be 9.28 m.
The First option may be correct. Im deeply sorry if im wrong!
FIRST OPTION (A)(1)
Answer: The balanced equation is
Au(s) + 3HNO3(aq) + 4HCl(aq) ---> HAuCl4(aq) + 3NO2(g) +3H2O(l)
The function of HCl in a solution of Aqua regia, that is used to dissolve gold is to dissolve other metals like quartz or iron stone that surround the gold.
Explanation: To balance the equation, we check the ratio of each element in the reacting side and the product side ( left and right hand side). Let their ratio be equal be adding moles to the compound of the element or the element it's self in either side of the equation.
HCl which is called hydrochloric acid, is an acid that does not react with gold, but it react with every other substance, like your skin, metals etc. it is used to clean a gold, by dipping the gold inside it, all the metals on the surface of the gold will dissolve.
When dissolving a gold in aqua regia solution, HCL is added to prepare this solution because it will help to dissolve all other substance on the surface of the gold.
C. Single-replacement
Chlorine replaces Bromine in KBr.