Answer:
17. D. Chemical change
18. C. Cell wall
19. D. To transfer matter and energy within and between organisms.
20. A. Transporting materials
21. C. Carbon dioxide
22. A. Cellular respiration
23. C. Produce food and give off oxygen
Explanation:
I have been able to supply the correct answers. The cell wall functions as a structure that provides structural support and protection to the cell. It is tough, flexible and at times rigid. In a chemical change, new materials with new properties are manufactured. So, the process of photosynthesis is a chemical change.
The endoplasmic reticulum actually transports material. It transports materials like protein and lipids made within the cell and sends it to where they are needed.
Carbon dioxide is the the gas that animals give off and plants use it during photosynthesis. Cellular respiration involves the activities that result to the breaking down of food in order to release energy.
Answer:
3.59x10^21 molecules
Explanation:
1mole of a substance contains 6.02x10^23 molecules.
Therefore, 1mole of C8H18 will also contain 6.02x10^23 molecules
1mole of C8H18 = (12x8) +(18x1) = 96 + 18 = 114g.
1mole (i.e 114g) oh C8H18 contains 6.02x10^23 molecules.
Therefore, 0.68g of C8H18 will contain = (0.68 x 6.02x10^23)/114 = 3.59x10^21 molecules
Answer:
pH = 12.15
Explanation:
To determine the pH of the HCl and KOH mixture, we need to know that the reaction is a neutralization type.
HCl + KOH → H₂O + KCl
We need to determine the moles of each compound
M = mmol / V (mL) → 30 mL . 0.10 M = 3 mmoles of HCl
M = mmol / V (mL) → 40 mL . 0.10 M = 4 mmoles of KOH
The base is in excess, so the HCl will completely react and we would produce the same mmoles of KCl
HCl + KOH → H₂O + KCl
3 m 4 m -
1 m 3 m
As the KCl is a neutral salt, it does not have any effect on the pH, so the pH will be affected, by the strong base.
1 mmol of KOH has 1 mmol of OH⁻, so the [OH⁻] will be 1 mmol / Tot volume
[OH⁻] 1 mmol / 70 mL = 0.014285 M
- log [OH⁻] = 1.85 → pH = 14 - pOH → 14 - 1.85 = 12.15
Answer:
CaCO3 is false
Explanation:
Because HCl is hydrongen chloride