Answer:
B carbon
Explanation
Lewis structure or dot structure is an easy way to get the bonding details of atoms in a molecule. If we talk about methane molecule carbon is central atom with four electrons that are bonded to four hydrogen atoms and each bond is single covalent bond.
Please see attached figure,
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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.
Answer:
0.00369 moles of HCl react with carbonate.
Explanation:
Number of moles of HCl present initially = 
moles = 0.00600 moles
Neutralization reaction (back titration): 
According to above equation, 1 mol of NaOH reacts with 1 mol of 1 mol of HCl.
So, excess number of moles of HCl present = number of NaOH added for back titration = 
moles = 0.00231 moles
So, mole of HCl reacts with carbonate = (Number of moles of HCl present initially) - (excess number of moles of HCl present) = (0.00600 - 0.00231) moles = 0.00369 moles
Hence, 0.00369 moles of HCl react with carbonate.
<span>The generalized reaction for chemical decomposition is: AB → A + B
NaOH is sodium hydroxide. When sodium and water is combined it makes sodium hydroxide and hydrogen
When sodium hydroxide decomposes under thermal decomposition, it breaks down into sodium oxide and water.
Thus, </span><span>C) 2NaOH Na2O + H2O</span>
