Answer: a) 
b) 
c)
d) 
e) 
Explanation:
A balanced nuclear equation is one in which the atomic number and mass number remains same on both sides of the equation i.e the number of protons and neutrons remain same.
General representation of an element is given as:
Z represents Atomic number
A represents Mass number
X represents the symbol of an element
a)
b) 
c) 
d)
e)
Answer: 72.4 kJ/mol
Explanation:
The balanced chemical reaction is,
The expression for enthalpy change is,
![\Delta H=\sum [n\times \Delta H_f(product)]-\sum [n\times \Delta H_f(reactant)]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H_f%28product%29%5D-%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H_f%28reactant%29%5D)
![\Delta H=[(n_{CO_2}\times \Delta H_{CO_2})+(n_{H_2O}\times \Delta H_{H_2O})]-[(n_{O_2}\times \Delta H_{O_2})+(n_{C_3H_8}\times \Delta H_{C_3H_8})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%28n_%7BCO_2%7D%5Ctimes%20%5CDelta%20H_%7BCO_2%7D%29%2B%28n_%7BH_2O%7D%5Ctimes%20%5CDelta%20H_%7BH_2O%7D%29%5D-%5B%28n_%7BO_2%7D%5Ctimes%20%5CDelta%20H_%7BO_2%7D%29%2B%28n_%7BC_3H_8%7D%5Ctimes%20%5CDelta%20H_%7BC_3H_8%7D%29%5D)
where,
n = number of moles
(as heat of formation of substances in their standard state is zero
Now put all the given values in this expression, we get
![-2220.1=[(3\times -393.5)+(4\times -241.8)]-[(5\times 0)+(1\times \Delta H_{C_3H_8})]](https://tex.z-dn.net/?f=-2220.1%3D%5B%283%5Ctimes%20-393.5%29%2B%284%5Ctimes%20-241.8%29%5D-%5B%285%5Ctimes%200%29%2B%281%5Ctimes%20%5CDelta%20H_%7BC_3H_8%7D%29%5D)
Therefore, the heat of formation of propane is 72.4 kJ/mol
Answer: 850.0 g/min.
Explanation:
- The rate of the reaction = (ΔC/Δt) where,
ΔC is the change in concentration of reactants or products.
Δt is the change in time of the reaction proceeding.
- The rate is needed to be calculated in (g/min).
- We need to calculate the amount of the product in (g) via using the relation (n = mass / molar mass).
- mass (g) = n x molar mass,
- n = 1.5 moles and molar mass of P₄O₁₀ = 283.88 g/mol.
- m = 1.5 x 283.88 = 425.82 g.
- ΔC = 425.82 g and Δt = 30 s / 60 = 0.5 min.
- The rate of the reaction = ΔC / Δt = (425.82 g / 0.5 min) = 851.64 g/min.
<em>can be approximated to 850.0 g/min.</em>
Burrows, tracks, coprolites, nests and footprints are examples of traces that can be found in a fossil.
I think false is the answer .if wrong correct meeee
