Explanation:
It is known that number of moles of a substance equal to mass divided by its molar mass.
Mathematically, No. of moles = 
It is given that no. of oles present are 27.2 mol and molar mass of N is 14 g/mol.
Therefore, calculate mass of N as follows.
No. of moles =
27.2 mol = 
mass = 380.8 g
Thus, we can conclude that mass of N is 380.8 g.
Answer:
Explanation:
for solutions in the same phase, the substance presents in lower concentration are solutes and the one in highest abundance is the solvent
Answer:
the molecules move more quickly and their average kinetic energy decreases :D
Explanation:
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
4.48
pH=pKa+log([A-/HA])
25% deprotonated tells us that A- is .25 and that the rest (75% is protonated) thats .75.
4 = pKa + log
4 - log
= pKa
4.48=pKa
