<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles. We calculate as follows:
0.340 mol Br2 ( </span>6.022 x 10^23 molecules / mol ) = 2.05 x 10^23 molecules
Answer:
2,3–dimethylpentane
Explanation:
To know which option is correct, we shall determine the name of the compound.
To obtain the name of the compound, do the following:
1. Determine the longest continuous carbon chain. This gives the parent name of the compound.
2. Identify the substituent group attached to the compound.
3. Locate the position of the substituent group by giving it the lowest possible count.
4. Combine the above to obtain the name of the compound.
Now, we shall determine the name of the compound as follow:
1. The longest continuous carbon chain is 5. Thus, the parent name of the compound is pentane.
2. The substituent group attached is methyl (–CH₃)
3. There are two methyl group attached to the compound. One is located at carbon 2 and the other at carbon 3.
4. Therefore, the name of the compound is:
2,3–dimethylpentane
None of the options are correct.
Answer: definite proportions.
Explanation:
1) The definite proportions law states that compounds will always have the same kind of atoms (elements) in the same mass proportion (ratios).
2) For example, a molecule of water will alwys have the same mass ratio of hydrogen atoms to oxygen atoms. That is what permits to obtain the chemical formula of the water molecule as H₂O.
The mass of the two hydrogen atoms will be in a fixed ratio respect to the mass of the oxygen atoms.
Then, if you have one reactant in less proportion than the other, respect to the ratio stated by the chemical formula of water, the former will react completely (it is the limiting reactant) with the corresponding (proportional) mass of the later. Then there will be an excess of the later reactant which will not react (will remain unchanged).
The reactants can only react in the proportion defined by the chemical formulas of the final products.
Meteorologists also use satellites to observe cloud patterns around the world, and radar is used to measure precipitation. All of this data is then plugged into super computers, which use numerical forecast equations to create forecast models of the atmosphere.
<span>If a neutral atom becomes negatively charged, it has undergone reduction.
Reduction is the process through which a neutral atom gain an electron (thus reducing its oxidation number) and turns into a negative ion (also known as : anion)</span>