Conduction - by touch
Convection - hot air rises, cold air sinks
Insulation - to insulate or capture heat
Radiation - by waves
Direct contact means touch, therefore the answer would be conduction.
Answer:
The solution is given below
Explanation:
Heat, q= mc∆T
q= 125g x 4.18 J/g∙°C x (21.18x- 24.28) °C
q= -1619.75J
NEGATIVE SIGN INDICATES THAT HEAT IS ABSORBED.
Enthalpy Change, ∆H = 1619.75 7/ 10.5 g
= 154.26 J/g
No. of moles of KBr = Mass of KBr/ Molecular Weight of KBr
=10.5g/119gmol-1
=0.088 mol
∆H= 1619.75 J/ 0.088 mol
= 18.41 kJ/mol
For a reaction to occur, there should be mobility of ions in reactant side.
If the reactant is larger, its mobility will be lesser than that of smaller ones.
So reactants smaller in size have higher mobility which makes reaction faster.
Hence D is the correct option.
Hope this helps, have a great day/night ahead!
Answer:
Sugar
Explanation:
Mixtures are substances that made of two or more elements or other substances that are joined together by physical methods and when mixed can be also be separated by physical method into the original individual elements.
Air is a mixture of gases such as oxygen, nitrogen, carbon dioxide and rare gases. When an amount of air is collected, its constituents can be collected separately.
Likewise 7 up and sea water
Sugar is a compound made of carbon, hydrogen and oxygen, when sugar is decomposed, it's original constituents are not recovered but sugar is decomposed into carbon dioxide and water
When an electrolyte dissolves in water, the resulting solution conducts an electric current.