The answer is 9. Calcium nitrate is made up
of 3 different elements that equal 9 atoms.
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:
0.056moles HF and 0.70M
Explanation:
When a strong acid is added to a buffer, the acid reacts with the conjugate base.
In the system, NaF and HF, weak acid is HF and conjugate base is NaF. The reaction of NaF with HCl (Strong acid) is:
NaF + HCl → HF + NaCl
Initial moles of NaF and HF in 60.0mL of solution are:
NaF:
0.0600L × (0.80mol / L)= 0.048 moles NaF
HF:
0.0600L × (0.80mol / L)= 0.048 moles HF
Then, the added moles of HCl are:
0.0200L × (0.40mol / L) = 0.008 moles HCl.
Thus, after the reaction, moles of HF produced are 0.008 moles + the initial 0.048moles of HF, moles of HF are:
<em>0.056moles HF</em>
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In 20.0mL + 60.0mL = 80.0mL = 0.0800L, molarity of HF is:
0.056mol HF / 0.0800L = <em>0.70M</em>
The core is the layer of the sun from which energy escapes into space.