Answer:
Amount left after 25 days = 12.5 g
Explanation:
Given data:
Mass of sample = 400 g
Half life of sample = 5 days
Mass left after 25 days = ?
Solution:
First of all we will calculate the number of half lives passes in given time period.
Number of half lives = Time elapsed / Half life
Number of half lives = 25 days/ 5 days
Number of half lives = 5
At time zero = 400 g
At 1st half life = 400 g/2 = 200 g
At 2nd half life = 200 g/2 = 100 g
At 3rd half life = 100 g/2 = 50 g
At 4th half life = 50 g/2 = 25 g
At 5th half life = 25 g/2 = 12.5 g
A Beta particles is emitted when an atom of 85Kr spontaneously decays.
Answer:
a) First-order.
b) 0.013 min⁻¹
c) 53.3 min.
d) 0.0142M
Explanation:
Hello,
In this case, on the attached document, we can notice the corresponding plot for each possible order of reaction. Thus, we should remember that in zeroth-order we plot the concentration of the reactant (SO2Cl2 ) versus the time, in first-order the natural logarithm of the concentration of the reactant (SO2Cl2 ) versus the time and in second-order reactions the inverse of the concentration of the reactant (SO2Cl2 ) versus the time.
a) In such a way, we realize the best fit is exhibited by the first-order model which shows a straight line (R=1) which has a slope of -0.0013 and an intercept of -2.3025 (natural logarithm of 0.1 which corresponds to the initial concentration). Therefore, the reaction has a first-order kinetics.
b) Since the slope is -0.0013 (take two random values), the rate constant is 0.013 min⁻¹:
c) Half life for first-order kinetics is computed by:
d) Here, we compute the concentration via the integrated rate law once 1500 minutes have passed:
Best regards.
For this problem, the solution is exhibiting some colligative properties since the solute in the solution interferes with some of the properties of the solvent. We use equation for the boiling point elevation for this problem. We do as follows:
<span>
ΔT(boiling point) = (Kb)mi
</span>ΔT(boiling point) = (0.512)(1.3/2.0)(2)
ΔT(boiling point) = 0.67 degrees Celsius
<span>
T(boiling point) = 100 + 0.67 = 100.67 degrees Celsius</span>
Answer:
<u>Physical Properties</u>
Alkali metals are good conductors of heat and electricity while halogens are poor conductors of heat and electricity.
Only specific to Alkali metals: They are soft and can be cut by knife.
<u>Chemical</u><u> </u><u>Properties</u>
Alkali metals have 1 valence electron while halogens have 7 valence electrons.
Alkali metals react with non-metals to form ionic compounds while halogens react with non-metals to form covalent compounds.
You can also look at the trends ( melting/boiling point, reactivity) down their group.
