Answer is: Zn + Cu2+ → Zn2+ + Cu.
In this chemical reaction, there is transfer of electrons from zinc (Zn) to copper (Cu). Zinc change oxidation number from 0 to +2 (lost electrons) and copper change oxidation number from +2 to 0 (gain electrons).
Oxidation half reaction: Zn⁰ → Zn²⁺ + 2e⁻.
Reduction half reaction: Cu²⁺ + 2e⁻ → Cu⁰.
In other chemical reactions, there is no change of oxidation number of elements.
The calories per gram of each substance are:
Protein: 4 calories / gram
Carbohydrates: 4 calories / gram
Fat: 9 calories / gram
So, one bar contains:
50 * 4 + 10 * 9 + 40 * 4
450 calories
If she were to eat only these bars, she will need:
2,700 / 450
= 6 nutrition bars for her climb
Answer:
Some chemicals react badly to your body, causing a chain of results leading to diseases.
Explanation:
The density of the carbon tetrachloride is 1.59 g/mL.
Mass of CCl₄ = 703.55 g – 345.8 g = 357.75 g
Density = mass/volume = 357.75 g/225 mL = 1.59 g/mL
