Answer:
number of hydrogen atom in 1.8 mole of NH2OH = 
Explanation:
percentage of hydrogen in NH2OH = mass of hydrogen / mass of whole molecule
=
\times 100
= 9.09 percentage
therefore number of moles in 1.8 moles of hydroxy amine = 
= .16 moles of hydrogen
number of hydrogen atom = (number of moles )×(avagadro number)
=
atoms of hydrogen
Answer:
ΔH is negative and ΔS is negative.
Explanation:
Endothermic reaction -
The type of reaction in which energy is absorbed in the form of heat is known as endothermic reaction .
The reaction mixture usually get cooled after the reaction .( temperature decreases ) .
The sign of ΔH of an Endothermic reaction is positive .
<u>For the of process of freezing the liquid ethanol , energy in the form of heat is released and hence , exothermic reaction ΔH is negative .</u>
<u>In the process of freezing , liquid is converted to solid , i.e. , the randomness reduces , and hence , entropy also decreases , hence , ΔS is negative .</u>
Answer:
.....false
Explanation:
the particles in the air are packed apart whereas the particles in steel are closely packed and sound travel faster in solids than in gasses..
Answer:
235 g
Explanation:
From the question;
- Volume is 400.0 mL
- Molarity of a solution is 4.25 M
We need to determine the mass of the solute K₂CO₃,
we know that;
Molarity = Number of moles ÷ Volume
Therefore;
First we determine the number of moles of the solute;
Moles = Molarity × volume
Moles of K₂CO₃ = 4.25 M × 0.4 L
= 1.7 moles
Secondly, we determine the mass of K₂CO₃,
We know that;
Mass = Moles × Molar mass
Molar mass of K₂CO₃, is 138.205 g/mol
Therefore;
Mass = 1.7 moles × 138.205 g/mol
= 234.9485 g
= 235 g
Thus, the mass of K₂CO₃ needed is 235 g