- Organic Chemistry
- Aldehydes and Ketones
- Alkyl Halides, Alcohols and ethers
- Amines and other nitrogen compounds
- Aromatic Chemistry
- Carbohydrates, Amino acids, protein, Vitamin and Fat
- Carboxylic acids and its derivatives
- Chemistry in daily life
- General Mechanism in organic compounds
- Hydrocarbons
- Nomenclature and isomerism
102 - Physical Chemistry Questions Answers
what is the ph of the solution formed by mixing 20 ml of 0.05 M H2SO4 with 5 ml of 0.45 M NaOH at 298 k ?
mili eq of acid = VN = 20*0.1 = 2
mili eq of base = VN = 5*0.45 = 2.25
total milieq = 2.25-2 = 0.25 of base in 25 ml
so N = 0.25/25 = 10-2
so pOH = 2 so pH = 12
1-In the following hypothetical reaction A + 3B --------------
A + 3B ---------> 2C + D
1 1/2 0 0
1-x 1/2-3x 2x x
according to the given condition 1/2 - 3x = 2x
so 1/10 = x
so 3x = 3/10
so % = 0.3*100/0.5 = 60
C2H4O --------------> CO + CH4
t P (C2H4O)
0 116.6
5 116.6-[122.56-116.6] = 116.6-5.96 = 110.64
7 116.6-[125.72-116.6] = 116.6-9.12 = 107.48
similarly others then find k for different readings by first order equation. k will be same for all readings.
why heat of an ideal solution is taken as zero ?
because in ideal solution there is no interaction between the two liquids present in the solution
The enthalpy of nuutralisation of a strong acid HA and weaker acid HB by KOH are -13.7 and -12.7 kcal/eq. When one equivalent of KOH is added to a mixture containing 1 eq of HA amd HB ; the enthaply change was -13.5 kcal. In what ratio is thge base distributeed between HA and HB ?
let x in HA and 1-x in HB
so according to the given condition -13.7x-12.7(1-x) = -13.5
solve
gas in gas is a solution but interaction between the molecules play almost no role so these solutions are addressed as mixtures
WHAT OSMOTIC PRESSURE WOULD BE OF 1.25m SUCROSE SOLUTION AT 25C ?DENSITY OF SOLUTION IS 1.34g/mL?
formula is πV = nRT or π = MRT, M is molarity
strength of solution is 1.25m
so 1000 gm water ..............................................1.25 mole sucrose
so 1000 gm water .............................................1.25*342=427.5gm sucrose
so 1427.5 gm solution ....................................1.25 mole sucrose
so 1427.5/1.34=1065.30 ml = 1.0653 L solution ...........................1.25 mole sucrose
so M = 1.25/1.0653
put all the values to get answer.
when 20 g of caco3 were put into 10 litre flask and heated to 800 degree cesius, 30% of caco3 remained unreacted at equilibrium. kp for decomposition of caco3 will be 1.231 ATM HOWWWW............PLS SOLVE THIS ....PLS PLS..........
CaCO3 ----------> CaO + CO2 (g)
0.2 mole 0 0
0.06 0.14 0.14
so Kp= p only CO2 is gas so its pressure is considered
now p = 0.14*0.0821*1073/10
now solve
0.25 g lyophilic colloid is added to 100 ml gold solution to prevent the coagulation on adding 1ml 10% NaCl soln . What will be gold number of lyophilic colloid??
“weight of the dried protective agent in milligrams, which when added to 10 ml of a standard gold sol (0.0053 to 0.0058%) is just sufficient to prevent a colour change from red to blue on the addition of 1 ml of 10 % sodium chloride solution, is equal to the gold number of that protective colloid.”
0.25 g lyophilic colloid is added to 100 ml gold solution
so 250 mg lyophilic colloid is added to 100 ml gold solution
so 25 mg lyophilic colloid is added to 10 ml gold solution
so answer will be 25
Most effective coagulant for a colloid soln of arsenic sulphide in water is
1) 0.1 M sodium phosphate
2) 0.1M zinc sulphate
3) 0.1 M zinc nitrate
4) 0.1 M aluminium chloride
Plzz annex explanation also
its 4th option
because As2S3 is usually a negative colloid and positive ion is responsible for its coagulation and according to Hardy Schulze priciple more positive ion will be more effective