This reaction does not exist since all of the reactants and products are aqueous.
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.
Answer:
Total energy consumed = 1,882.8 joules
Explanation:
Given:
Calories burned = 450 calories
Find:
Total energy consumed
Computation:
1 calorie = 4.184 joules
So,
450 calories = 4.184 × 450
450 calories = 1,882.8 joules
Total energy consumed = 1,882.8 joules
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Answer:
C5H7N
C10H14N2
Explanation:
ok so lets lay out this nicely
elements C H N
percentage 74 8.7 17.3
mass number 12 1 14
divided percentage by mass 6.167 8.7 1.2357
now divide the smallest number with the 4.99 7.04 1
rest for instance 1,237 is the smallest.
so 6.167÷1,237
and 8.7 ÷1.237
and 1,237 divide 1.237
now the ratio is C5H7N
now for molecular formula find Mr of C5H7N which is (12×5)+7+14=81
next divide 162.1÷81=2
so now for molecular formula just multipily everythng by 2
C10H14N2