To determine which order of the reaction it is, first we need to calculate the rate of change of moles.
the data is as follows
time 0 40 80 120 160
moles 0.100 0.067 0.045 0.030 0.020
Q1)
for the first 40 s change of moles ;
= -d[A] / t
= - (0.067-0.100)/40s
= 8.25 x 10⁻⁴ mol/s
for the next 40 s
= -(0.045-0.067)/40
= 5.5 x 10⁻⁴ mol/s
the 40 s after that
= -(0.030-0.045)/40 s
= 3.75 x 10⁻⁴ mol/s
k - rate constant
and A is the only reactant that affects the rate of the reaction
rate = k [A]ᵇ
8.25 × 10⁻⁴ mol/s = k [0.100 mol]ᵇ ----1
5.5 x 10⁻⁴ mol/s = k [0.067 mol]ᵇ -----2
divide the 2nd equation by the 1st equation
1.5 = [1.49]ᵇ
b is almost equal to 1
Therefore this is a first order reaction
Q2)
to find out the rate constant(k), we have to first state the equation for a first order reaction.
rate = k[A]ᵇ
As A is the only reactant thats considered for the rate equation.
Since this is a first order reaction,
b = 1
therefore the reaction is
rate = k[A]
substituting the values,
8.25 x 10⁻⁴ mol/s = k [0.100 mol]
k = 8.25 x 10⁻⁴ mol/s /0.100mol
= 8.25 x 10⁻³ s⁻¹
Answer:
I think that middle school teachers are interested in teaching middle schoolers.
Answer:
Only white phosphorus is stored under water. White phosphorus spontaneously reacts with oxygen in the air to burst into flame to form phosphorus pentoxide
Explanation:
Answer and Explanation:
Two hydrogen atoms, each containing one electron, approach each other in the formation of a molecule of hydrogen. Each atom needs a total of two electrons to fill their outermost energy level and make them stable. The best choice is to share their single electrons. Hence, a pair of bonding electrons is shared between the hydrogen atoms in the molecules.
This constitutes a single covalent bond. Hence, the correct option is B)
You must first know that the number of protons and neutrons are same, and neutrons number may vary. Carbon 12 has 6 protons, 6 neutrons and 6 electrons. Sodium 23 has 12 protons , 12 electrons and and 11 neutrons. Silver 108 has 47 protons, 47 electrons and 61 electrons. Finally, Sulfur 32 has 16 protons, 16 nuetrons and 16 electrons. Basically the number of neutrons in an atom can be found by subtracting proton number from mass number