An ionic compound is composed of ionic bonds that are formed by transfer of electrons from one atom to the other. The atom that loses electrons acquires a positive charge (cation) while that which gains electrons acquires a negative charge.
In the case of sodium chloride; Sodium Na has 1 electron in its outer orbital while Chlorine Cl has 7 electrons. Thus, Cl requires 1 electron to complete its octet. This electron is donated by Na.
Thus, NaCl is essentially, Na⁺Cl⁻
Ans D) Chlorine becomes an anion by gaining an electron from sodium
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 : The time required for decay is, 84 days.
Explanation :
Half-life of chromium-51 = 28 days
First we have to calculate the rate constant, we use the formula :
Now we have to calculate the time required for decay.
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = time taken by sample = ?
a = let initial activity of the sample = 100
a - x = amount left after decay process = 12.5
Now put all the given values in above equation, we get
Therefore, the time required for decay is, 84 days.
You just switch them around
