Answer:
28.75211 kj
Explanation:
Given data:
Mass of iron bar = 841 g
Initial temperature = 84°C
Final temperature = 7°C
Heat released = ?
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 iron is 0.444 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 = 7°C - 84°C
ΔT = -77°C
By putting values,
Q = 841 g × 0.444 j/g.°C × -77°C
Q = 28752.11 j
In Kj:
28752.11 j × 1 kJ / 1000 J
28.75211 kj
Answer: -
Hydrogen peroxide breaks down into water and oxygen.
2H₂O₂ → 2H₂O + O₂
The yeast present contains an enzyme called catalase which catalyses the reaction.
More the amount of the catalyst added, faster will be the decomposition of the hydrogen peroxide.
Thus if we added more than 5 mL of yeast solution to the 2H₂O₂, the breakdown would occur faster. Thus the bubbles and the accompanying fizz would be much more.
it is b forces hold matter together
A force is a push or pull on an object. Forces usually cannot be seen but their effects can. Nothing moves, changes speed, stops or changes direction without force. Heavier objects need more force to get them to move or change direction.
this is the answer is
Zn<span> + </span>HCl<span> = </span>ZnCl2<span> + </span>H2 <span> </span>
Answer:
Option C. By increasing the temperature
Explanation:
From the graphical illustration above, we see clearly that the volume and temperature of the gas are directly proportional. This implies that as the temperature increases, the volume will also increase and as the temperature decreases, the volume will also decrease. This can further be explained by using the ideal gas equation as shown below:
PV = nRT
P is the pressure.
V is the volume.
n is the number of mole.
R is the gas constant.
T is the temperature.
PV = nRT
Divide both side by P
V = nRT/P
Since n and P are constant, the equation above becomes:
V & T
V = KT
K is the constant.
The above equation i.e V = KT implies that:
As T increases, V will also increase and as T decreases, V will also decrease.
Considering the question given above,
The volume of the gas can be increased if the temperature is increased.
