Ca(OH)₂ = Ca²⁺ + 2OH⁻
[OH⁻]=2c{Ca(OH)₂}
pH=14+lg[OH⁻]
pH=14+lg(2c{Ca(OH)₂})
pH=14+lg(2*0.0075)=12.18
Answer:
The concentration of H3O+= 0.15M
Explanation:
From The equation of reaction
HClO2(aq) + H2O(l) ⇌ H3O+(aq) + ClO2−(aq)
0.25mol HClO2(aq) 0.25mol producesClO2−(aq) and x-mol of H3O+
Using Kc = [H3O+][ClO2-]/[HClO2]
0.15= 0.25*x/0.25
Simplify
x=0.15M
Answer:
A. They must be kept separate from moisture and oxygen
Explanation:
Alkali metals refers to a group of chemical elements in the periodic table. It is the common name given to Group 1 elements (excluding hydrogen). They are generally metallic in nature with physical properties like shining lustre, silvery in appearance etc. Alkali metals include lithium, Pottasium, Sodium, Rubidium etc.
One important chemical property of alkali metals is their high reactivity i.e. they tend to react quickly with other substances. For example, alkali metals react vigorously with water to form hydroxides. They also react with oxygen to form oxides. Due to this highly reactive properties, they are kept or stored away from moisture (water) and oxygen (present in air).
Answer:
Total of all numbers added with the correct rounding and number of significant figures
Explanation:
1. Add up all the numbers
8.32+8.00+8.30+8.3
2. Determine how many significant figures should be in your final answer. When it comes to addition, it will be the fewest number of decimal places. since 8.3 has one decimal place, your final answer should only have one decimal place.
3. Round your final answer to the nearest tenths
Answer:
The answer to your question is letter A
Explanation:
Abundance Atomic mass
V-50 0.25% 49.947
V-51 99.750% 50.944
Formula
Average atomic mass = [V-50-Abundance x V-50-Atomic mass] +
[ V-51-Abundance x V-51-Atomic mass]
Substitution
Average atomic mass = [ 0.0025 x 49.947] + [0.9975 x 50.944]
= 0.125 + 50.817
Result
= 50.942 amu
