Answer:
1.6g/mL
Explanation:
Density equation is D=m/v
Density = g/mL
m=mass of sample in grams
v = volume of sample in mL
The volume of a square can be calculated by V=l*w*h.
In this case it is 5cm*5cm*5cm = 125cm^3
Since we know that 1cm^3 ~ 1mL we can convert the volume to mL as so:
125cm^3 (1mL/(1cm^3)) = 125mL
Then simply plug into the density equation:
D=200g/125mL = 1.6g/mL
The answer is A. the attraction between atoms that enables the formation of chemical compounds.
Answer:
K₂CrO₅
Explanation:
The empirical formula is the simplest formula of a compound. To find the empirical formula, we follow the procedure below:
Elements Potassium Chromium Oxygen
Mass 6.52 4.34 5.34
Molar mass 39 60 16
Number of moles 6.52/39 4.34/60 5.34/16
0.167 0.072 0.333
Divide through by
the smallest 0.167/0.072 0.072/0.072 0.333/0.072
2.3 1 4.6
2 1 5
Empirical formula K₂CrO₅
The below is about the energy exchanges in earth systems.
<u>Explanation</u>:
- Energy exchanges in earth systems are of many types. The earth systems are atmosphere, geosphere, stratosphere, hydrosphere, and biosphere. All these earth systems exchange energy with each other.
- The earth gains energy reflected from the sky. It converts that energy back to space. That energy is equally given to all the planets in the sky.
- Each planet will absorb that energy and radiate heat. This heat is absorbed by all the places on the earth. So this is the energy exchange in the earth systems.
Answer:
pH = 13.09
Explanation:
Zn(OH)2 --> Zn+2 + 2OH- Ksp = 3X10^-15
Zn+2 + 4OH- --> Zn(OH)4-2 Kf = 2X10^15
K = Ksp X Kf
= 3*2*10^-15 * 10^15
= 6
Concentration of OH⁻ = 2[Ba(OH)₂] = 2 * 0.15 = 3 M
Zn(OH)₂ + 2OH⁻(aq) --> Zn(OH)₄²⁻(aq)
Initial: 0 0.3 0
Change: -2x +x
Equilibrium: 0.3 - 2x x
K = Zn(OH)₄²⁻/[OH⁻]²
6 = x/(0.3 - 2x)²
6 = x/(0.3 -2x)(0.3 -2x)
6(0.09 -1.2x + 4x²) = x
0.54 - 7.2x + 24x² = x
24x² - 8.2x + 0.54 = 0
Upon solving as quadratic equation, we obtain;
x = 0.089
Therefore,
Concentration of (OH⁻) = 0.3 - 2x
= 0.3 -(2*0.089)
= 0.122
pOH = -log[OH⁻]
= -log 0.122
= 0.91
pH = 14-0.91
= 13.09
