Answer:
if you mix any halogen with any alkali then ionic salt will be formed and also this will cause an exothermic reaction in which heat is getting released
A substance that contains two or more kinds of atoms is a molecule.
Answer:
1 = Q = 7315 j
2 =Q = -21937.5 j
Explanation:
Given data:
Mass of water = 50 g
Initial temperature = 20°C
Final temperature = 55°C
Energy required to change the temperature = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Specific heat capacity of water is 4.18 j/g.°C.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = T2 - T1
ΔT = 55°C - 20°C
ΔT = 35°C
Q = 50 g× 4.18 j/g.°C×35°C
Q = 7315 j
Q 2:
Given data:
Mass of metal = 100 g
Initial temperature = 1000°C
Final temperature = 25°C
Energy released = ?
Specific heat capacity = 0.225 j/g.°C
Solution:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = T2 - T1
ΔT = 25°C - 1000°C
ΔT = -975°C
Now we will put the values in formula.
Q = 100 g × 0.225 j/g.°C × -975°C
Q = -21937.5 j
Negative sign show that energy is released.
Okay
Mr (H2O)= 18g
therefore moles of H2O
is 720.8/18= 40.04mol
the ratio of H2 to O2 to H2O is
2 : 1 : 2
so moles of H2 is same as H2O here
H2= 40.04moles
moles of O2 is half
so 40.04 x 0.5
20.02moles
grams of O2 is
its moles into Mr of O2
that's 20.02 x 32 = 640.64g
