Answer:
t = 7.58 * 10¹⁹ seconds
Explanation:
First order rate constant is given as,
k = (2.303
/t) log [A₀]
/[Aₙ]
where [A₀] is the initial concentraion of the reactant; [Aₙ] is the concentration of the reactant at time, <em>t</em>
[A₀] = 615 calories;
[Aₙ] = 615 - 480 = 135 calories
k = 2.00 * 10⁻²⁰ sec⁻¹
substituting the values in the equation of the rate constant;
2.00 * 10⁻²⁰ sec⁻¹ = (2.303/t) log (615/135)
(2.00 * 10⁻²⁰ sec⁻¹) / log (615/135) = (2.303/t)
t = 2.303 / 3.037 * 10⁻²⁰
t = 7.58 * 10¹⁹ seconds
Answer:
Towards the big bully
Explanation:
If a big bully and a small child are involved in a thug of war, it is clear that the bully is stronger than the child and he/she will pull the rope used in the thug of war with a greater force.
By so doing, the ball attached at the centre of the rope will naturally be drawn towards the stronger bully.
The molarity of NaOH needed is calculated as follows
calculate the moles of KhC8h4O4
that is moles = mass/molar mass of KhC8h4O4(204.22 g/mol)
=0.5632g /204.22g/mol= 2.76 x10^-3 moles
write the equation for reaction
khc8h4O4 + NaOH ---> KNaC8h4O4 + H2O
from the equation above the reacting ratio of KhC8h4O4 to NaOh is 1:1 therefore the moles of Naoh is also 2.76 x10^-3 moles
molarity of NaOh = (moles of NaOh / volume ) x 1000
that is { (2.76 x10^-3) / 23.64} x100 =0.117 M
Physical<span> changes involve a new </span>form<span> or shape of matter,
</span>
Chemical change<span> is any </span>change<span> that results in the formation of new </span>chemical<span> substances.</span>
