Mass of CaCl₂ = 0.732 g
<h3>Further explanation</h3>
The concentration of a substance can be expressed in several quantities such as moles, percent (%) weight / volume,), molarity, molality, parts per million (ppm) or mole fraction. The concentration shows the amount of solute in a unit of the amount of solvent.

Answer:
3.10×10¯⁵ ft³.
Explanation:
The following data were obtained from the question:
Density (D) of lead = 11.4 g/cm³
Mass (m) of lead = 10 g
Volume (V) of lead =.?
Density (D) = mass (m) / Volume (V)
D = m/V
11.4 = 10 / V
Cross multiply
11.4 × V = 10
Divide both side by 11.4
V = 10 / 11.4
V = 0.877 cm³
Finally, we shall convert 0.877 cm³ to ft³. This can be obtained as follow:
1 cm³ = 3.531×10¯⁵ ft³
Therefore,
0.877 cm³ = 0.877 cm³ × 3.531×10¯⁵ ft³ /1 cm³
0.877 cm³ = 3.10×10¯⁵ ft³
Thus, 0.877 cm³ is equivalent to 3.10×10¯⁵ ft³.
Therefore, the volume of the lead in ft³ is 3.10×10¯⁵ ft³.
Answer:
PH= 6.767 (answer is the A option)
Explanation:
first we need to correct the value in Kw at this temperature is 2.92*10^-14
so, in this case we have that:
Kw=2.92*10^-14 M²
[ H3O^+] [ H3O^+]
![[H_{3}O^{+} ] [OH^{-} ] = Kw = 2.92*10^{-14} M^{2} \\\\](https://tex.z-dn.net/?f=%5BH_%7B3%7DO%5E%7B%2B%7D%20%20%5D%20%5BOH%5E%7B-%7D%20%20%5D%20%3D%20Kw%20%3D%202.92%2A10%5E%7B-14%7D%20M%5E%7B2%7D%20%20%20%5C%5C%5C%5C)
at 40ºC
![[H_{3}O^{+} ] = [OH^{-} ]](https://tex.z-dn.net/?f=%5BH_%7B3%7DO%5E%7B%2B%7D%20%20%5D%20%3D%20%5BOH%5E%7B-%7D%20%20%5D)
![[H_{3}O^{+} ]^{2} = 2.92*10^{-14} M^{2}](https://tex.z-dn.net/?f=%5BH_%7B3%7DO%5E%7B%2B%7D%20%20%5D%5E%7B2%7D%20%3D%202.92%2A10%5E%7B-14%7D%20M%5E%7B2%7D)
![[H_{3}O^{+} ] = (2.92*10^{-14})^{1/2} = 1.71*10^{-7} M](https://tex.z-dn.net/?f=%5BH_%7B3%7DO%5E%7B%2B%7D%20%20%5D%20%3D%20%282.92%2A10%5E%7B-14%7D%29%5E%7B1%2F2%7D%20%3D%201.71%2A10%5E%7B-7%7D%20M)
![PH= -log10[H_{3}O^{+} ] = -log10(1.71*10^{-7} ) = 6.767](https://tex.z-dn.net/?f=PH%3D%20-log10%5BH_%7B3%7DO%5E%7B%2B%7D%20%20%5D%20%3D%20-log10%281.71%2A10%5E%7B-7%7D%20%29%20%3D%206.767)
Answer:
- Third choice:<em> energy present in the glucose and oxygen that is not needed for the formation of carbon dioxide and water is released to form energy/ATP.</em>
Explanation:
<u>1) Chemical equation (given):</u>
- C₆H₁₂O₆ + 6 O₂ --> 6 CO₂ + 6 H₂O + energy
<u>2) Chemical potential energy:</u>
Each compound stores chemical potential energy. This energy is stored in the chemical bonds.
Due to every substance has its own unique chemical potential energy, when a chemical reaction takes plase, yielding to the change of some substances, some energy is absorbed (when bonds are formed) and some energy is released (when bonds are broken).
<u>3) Conservation of energy:</u>
Then, if the sum of the bond energies of the final products is less than the sum of the bond energies of the reactants, the<em> law of conservation of energy</em> rules that the difference between the total energies of the products and reactants must be released to the surroundings.
That is what is happening in the given reaction:
- C₆H₁₂O₆ + 6 O₂ --> 6 CO₂ + 6 H₂O + energy
The term energy in the product side means that energy is conserved because it is being released due to the the glucose and oxygen (reactant side) have more energy stored in their bonds than the energy needed for the formation of carbon dioxide and water, so that excess of energy is released to form energy/ATP.
<u>Summarizing:</u>
- The energy on the product side added to the energy of carbon dioxide and water equals the energy of the glucose and oxygen and the final balance is:
- ∑ Energy of the reactants = ∑energy of the products + released energy, supporting the law of conservation of energy.
Answer:
heat
Explanation:
because it's the cause of change