<span>a) Table salt: it is a compound. A compound is a combination of atoms in fixed proportions.Table salt is NaCl, which means that table salt is a compound of 1 atom of Na and 1 atom of Cl and not other thing. b) Blood: is an homogeneous mixture: it is a mixture of many compounds which can not be easily distinguished or separated, you need microscopes or very special physical methods to distinguish or separate the different compounds of blood. d) Steel: it is a special king of homogeneous mixture (it is called an alloy) which, as in the case of blood, cannot be distinguished or separated easily. d) Planet earth: it is a heterogeneous mixture. You can easily distinguish many of the compounds of the planet Earth: water, oxygen, carbon,...</span><span />
Answer:
Photosynthetic bacteria must take in <u>Carbon Dioxide</u> to live, and they release <u>Oxygen </u> . Animals must take <u>Oxygen </u> to live, and they release <u>Carbon Dioxide.</u>
Explanation:
Photosynthesis:
It is the process in which in the presence of sun light and chlorophyll by using carbon dioxide and water plants produce the oxygen and glucose.
Carbon dioxide + water + energy → glucose + oxygen
water is supplied through the roots, carbon dioxide collected through stomata and sun light is capture by chloroplast.
Chemical equation:
6H₂O + 6CO₂ + energy → C₆H₁₂O₆ + 6O₂
Photosynthetic bacteria perform same function as plants. These bacteria contain light harvesting pigments absorb carbon dioxide and release oxygen.
While animals take oxygen and release carbon dioxide to live. This respiration process is opposite to the photosynthesis.
Glucose + oxygen → carbon dioxide + water + 38ATP
Fireworks
An exothermic reaction is one where the products have lower energy than the reactants, so the reaction yields energy. The chemical compounds present in firework fuel release a lot of energy upon oxidation. Photosynthesis is endothermic, settling of silt is not a chemical reaction, it is a physical change. Finally, the bubble formation in soda is not exothermic; otherwise, the sodas would become very hot very fast.
Answer:
A) Very stable.
Explanation:
A valence electron ring takes up to 8 valence electrons. If it has full rings, it is stable.
<h3>
Answer:</h3>
42960 years
<h3>
Explanation:</h3>
<u>We are given;</u>
- Remaining mass of C-14 in a bone is 0.3125 g
- Original mass of C-14 on the bone is 80.0 g
- Half life of C-14 is 5370 years
We are required to determine the age of the bone;
- Remaining mass = Original mass × 0.5^n , where n is the number of half lives.
Therefore;
0.3125 g = 80.0 g × 0.5^n
3.90625 × 10^-3 = 0.5^n
- Introducing logarithm on both sides;
log 3.90625 × 10^-3 = n log 0.5
Solving for n
n = log 3.90625 × 10^-3 ÷ log 0.5
= 8
- Therefore, the number of half lives is 8
- But, 1 half life is 5370 years
- Therefore;
Age of the rock = 5370 years × 8
= 42960 years
Thus, the bone is 42960 years old