Answer : The correct option is A.
Explanation :
Enzyme-catalyzed reaction :
Enzyme act as a biological catalyst and the role of catalyst is to increase the rate of chemical reaction by lowering the activation energy.
Most of the chemical reactions are slow in the absence of enzyme but in the presence of enzyme, the reaction become faster. That means the Enzyme accelerate the rate of reaction.
Therefore, the correct answer is the reaction is faster than the same reaction in the absence of the enzyme.
The atomic mass on the periodic table represents the sum of number of protons and number of neutrons.
Atomic mass = Number of protons + number of neutrons
Hope this helps!
Waste materials, mining and transportation of radioactive fuels, radiation emissions from nuclear sites
Answer: The number of grams of
in 1620 mL is 1.44 g
Explanation:
According to ideal gas equation:

P = pressure of gas = 1 atm (at STP)
V = Volume of gas = 1620 ml = 1.62 L (1L=1000ml)
n = number of moles = ?
R = gas constant =
T =temperature =


Mass of hydrogen =
The number of grams of
in 1620 mL is 1.44 g
Answer is: 25,06 kJ of energy must be added to a 75 g block of ice.
ΔHfusion(H₂O) = 6,01 kJ/mol.
T(H₂O) = 0°C.
m(H₂O) = 75 g.
n(H₂O) = m(H₂O) ÷ M(H₂O).
n(H₂O) = 75 g ÷ 18 g/mol.
n(H₂O) = 4,17 mol.
Q = ΔHfusion(H₂O) · n(H₂O)
Q = 6,01 kJ/mol · 4,17 mol
Q = 25,06 kJ.