Answer: 0.548J/g°C
Explanation:
Q = s × m × DeltaT
Q = Heat (J)
S = Specific Heat Capacity
M = mass (g)
DeltaT = Change in temperature (°C)
0.158Kg x 1000 = 158g
2.510J = s x 158g x (61°C-32°C)
2.510J/(158g x 29°C) = s
S = 0.54779.... J/g°C
S = 0.548 J/g°C
Answer:
See explanation
Explanation:
2HCl(aq) + CaCO3(aq) ------->CaCl2(aq) + CO2(g) + H2O(l)
Number of moles of acid present = 50/1000 * 0.15 = 0.0075 moles
Number of moles of calcium carbonate = 0.054g/100 g/mol = 0.00054 moles
2 moles of HCl reacts with 1 mole of calcium carbonate
x moles of HCl reacts with 0.00054 moles of calcium carbonate
x = 2 * 0.00054/1
x = 0.00108 moles of HCl
Amount of acid left = 0.0075 moles - 0.0075 moles = 0.00642 moles
Reaction of HCl and NaOH
HCl(aq) + NaOH(aq) ------> NaCl(aq) + H2O(l)
Since the reaction is in the mole ratio of 1:1
0.00642 moles of HCl is neutralized by 0.00642 moles of NaOH
Answer:
E. Evaporation to dryness
Explanation:
E. - Evaporation to dryness is the best method for the recovery of solid KNO3 from an aqueous solution of KNO3.
(KNO3 is very soluble, and will violently decompose if overheated.)
Paper chromatography is for separation of different weight molecules in solution.
B. Filtration won't work on a solution
C.Titration would contaminate the salt with something else and is used
to determine concentrations
D. Electrolysis would destroy the salt
Yes , the chemist can answer if the compound in K2O or K2O2
The chemical formula and composition of both the compounds is entirely different. The compound K2O2 has an additional molecule of oxygen than K2O and hence will have have higher molecular mass.
In the compound K2O
molecular mass= 2x 39+16 =94
mass ratio of K in compound= 78/94 = 0.830
In the compound K2O2
molecular mass= 2x 39+16X2 =110
mass ratio of K in compound= 78/110 = 0.710
and hence by the required ratio while extracting K , the chemist may know if the compound is K20 or K2O2
If the ratio is anything different from 0.830 and 0.710 then the compund will be something different
#SPJ9
mol = conc × v
= 1.5 × 0.09
= 0.135 moles of HCl
HCl + NaOH > NaCl + H2O
1 mole HCl = 1 mole NaOH
0.135 mol HCl = x
x = 0.135 mol NaOH
mass = mol × molar mass
= 0.135 × 40
= 5.4 g
NaOH = 23 + 16 + 1 = 40 g/mol
I'm not a 100% sure if it's correct
