Answer:
0.625 g
Explanation:
Given data:
Half life of radon-222 = 3.8 days
Total mass of sample = 10 g
Mass left after 15.2 days = ?
Solution:
Number of half lives = T elapsed / Half life
Number of half lives = 15.2 / 3.8
Number of half lives = 4
At time zero = 10 g
At first half life = 10 g/2 = 5 g
At 2nd half life = 5 g/ 2= 2.5 g
At third half life = 2.5 g/2 = 1.25 g
At 4th half life = 1.25 g/2 = 0.625 g
Decantation<span>Decantation is a process for the separation of mixtures, by removing a layer of liquid, generally one from which a precipitate has settled. The purpose may be either to produce a clean decant, or to remove undesired liquid from the precipitate (or other layers). Separate liquids
so it is false</span>
The information given in the question is not enough to determine the acidity of the solution. This is because, acidity can only be found with the equation: pH = -log [H+].
In order to determine the acidity of the solution, the half titration point value is needed, this will make it possible to determine the value of H30+. If the half point titration value is known, then Ka will be equivalent to pH and the value will be evaluated using the equation: - log (1.6 * 10^-10).
Answer:
Unlike isopropanol, hydrogen peroxide is not a type of alcohol. You might recognize its chemical formula, H2O2, as being similar to that of water (H2O). The difference is that hydrogen peroxide has two oxygen atoms instead of one. That one extra oxygen atom makes it a strong oxidizer.
Answer:
89.34%
Explanation:
First, write a balanced reaction.
Mg3N2 + <u>6</u>H2O --> <u>3</u>Mg (OH)2 + <u>2</u>NH3
Next determine the moles of the known substance, or limiting reagent ( H2O)
n= m/MM
n ( H2O) = 4.33/(1.008×2)+16
n(H2O)= 0.2403
Use the mole ratio to find the moles of Mg(OH)2
0.2403 ÷2
n (Mg (OH)2) = 0.1202
Next, find the theoretical mass of Mg (OH)2 that should have been produced
m= n × MM
m= 0.1202 × (24.305 + (16×2) +(1.008 ×2))
=7.007g
To find percentage yield, divide the experimental amount by the theoretical amount and multiply by 100.
6.26/ 7.007 × 100
=89.34%
