Answer: c. Some health risks are increased by heredity, which manifest under certain environmental conditions.
Explanation:
Many abiotic factors (non-living factors) such as radiations, hazardous substances present in the environment such as air, water and soil may originate from the industries, mining practices, fossil fuels and landfills. Some of the substances are carcinogenic and mutagenic in nature. These are capable of affecting the genetic make up of the organism. The genetic variations or mutations occurs may transmit from the parent to the offsprings.
Therefore, on the basis of the above information, c. Some health risks are increased by heredity, which manifest under certain environmental conditions. is the correct option.
The average mass of an atom is calculated with the formula:
average mass = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2) + ... an so on
For the boron we have two isotopes, so the formula will become:
average mass of boron = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2)
We plug in the values:
10.81 = 0.1980 × 10.012938 + 0.8020 × mass of isotope (2)
10.81 = 1.98 + 0.8020 × mass of isotope (2)
10.81 - 1.98 = 0.8020 × mass of isotope (2)
8.83 = 0.8020 × mass of isotope (2)
mass of isotope (2) = 8.83 / 0.8020
mass of isotope (2) = 11.009975
mass of isotope (1) = 10.012938 (given by the question)
Answer: Eutrophication is the enhancement of the growth of algae in the water body.
Explanation:
The scientists are worried for the climate change as if the climate changed to prolonged rainy then the frequent raining can remove toxic chemicals from the agricultural sites, landfills, industries, and from other locations and deposit them to the water body (river, lakes, ponds, and others). The deposition of the salts of nitrogen, phosphorus, and sulfur promotes the growth of algae in the water body. This leads to reduction in the concentration of oxygen in the water body. This is called eutrophication. The lack of oxygen can lead to mortality of aquatic animals.
4. A
because PbCl2 is an ionic compound and it's solid, so it's a substance.
It cannot be mixture, because it's a pure molecule.
5. D
despite that both substances are gases, colorless they are different molecules, so they should have different either chemical and physical properties
6. C
this substance made from W atoms and others are made from molecules
Answer:
Option D. pH= 1.3 strong acid
Explanation:
From the question given:
The hydrogen ion concentration [H+] = 0.05 M
pH = —Log [H+]
pH = —Log 0.05
pH = 1.3
Since the pH lies between 0 and 7, the solution is acidic. Since the pH value is low, the solution is a strong acid
