Answer:
C
Explanation:
A fuel cell uses both hydrogen and oxygen as fuels. At the cathode oxygen is reduced to water according to the equation
O2+4H^+ +4e ------>2H2O
And hydrogen is oxidized at the anode:
2H2------>4H^+ +4e
Fuel cells produce only water as a by product hence they are environment friendly
Correct answer is <span>X = ΔH
Reason:
1) The graph of enthalpy Vs reaction coordinate suggest the reaction is endothermic in nature. For endothermic reaction, energy if product is more than that of reactant. Hence, option 1 i.e. </span><span>X = -ΔH cannot be correct.
2) Since the reaction is endothermic in nature, </span>energy if product is more than that of reactant. Hence, option 2 i.e. X = ΔH is correct.
3) Activation energy is energy difference between Reactant (A) and transition state (B). However, as per option C, activation energy (A.E.) is energy difference between product (C) and transition state (B), which is incorrect.
Answer:
2. B It is the outermost layer of Earth, composed of solid rock and divided into sections called plates. 3. B The inner core is kept solid by the intense pressure of all the layers above it.
Explanation:
Answer:
C₅ H₁₂ O
Explanation:
44 g of CO₂ contains 12 g of C
30.2 g of CO₂ will contain 12 x 30.2 / 44 = 8.236 g of C .
18 g of H₂O contains 2 g of hydrogen
14.8 g of H₂0 will contain 1.644 g of H .
total compound = 12.1 out of which 8.236 g is C and 1.644 g is H , rest will be O
gram of O = 2.22
moles of C, O, H in the given compound = 8.236 / 12 , 2.22 / 16 , 1.644 / 1
= .6863 , .13875 , 1.644
ratio of their moles = 4.946 : 1 : 11.84
rounding off to digits
ratio = 5 : 1 : 12
empirical formula = C₅ H₁₂ O
