Answer:
(a) -0.00017 M/s;
(b) 0.00034 M/s
Explanation:
(a) Rate of a reaction is defined as change in molarity in a unit time, that is:
Given the following reaction:
We may write the rate expression in terms of reactants firstly. Since reactants are decreasing in molarity, we're adding a negative sign. Similarly, if we wish to look at the overall reaction rate, we need to divide by stoichiometric coefficients:
Reaction rate is also equal to the rate of formation of products divided by their coefficients:
Let's find the rate of disappearance of the reactant firstly. This would be found dividing the change in molarity by the change in time:
(b) Using the relationship derived previously, we know that:
Rate of appearance of nitrogen dioxide is given by:
Which is obtained from the equation:
If we multiply both sides by 4, that is:
This yields:
[tex]r_{NO_2} = \frac{\Delta [NO_2]}{\Delta t} = -2\frac{\Delta [N_2O_5]}{ \Delta t} = -2\cdot (-0.00017 M/s) = 0.00034 M/s[tex]
In alpha and beta decay the parent element and the daughter element will be different isotope and not the same.
This is because as alpha particles comes out; the new element will have two less in atomic number; that is the atomic number will reduce by two and the mass number will reduce by four. While in a beta particle decay, the new element will have one higher in atomic number; that is the atomic number will increase by one.
<h3>Answer:</h3>
Ca²⁺
<h3>Explanation:</h3>
Ionization energy is defined as the minimum amount of energy required to knock out the electron from valence shell of an atom in its gaseous state. While, second Ionization energy is defined as the amount of energy required to knock out the second electron from an ion containing +1 charge in gaseous state.
Among given options Ca²⁺ is the correct choice because the calcium has lost two electrons i.e. first electron was removed by providing first ionization energy i.e.
Ca + 1st IE → Ca¹⁺ + 1 e⁻
and second electron is was removed by providing second ionization energy i.e.
Ca ¹⁺ + 2nd IE → Ca²⁺ + 1 e⁻