A) 21
Explanation:
The difference between the number of electrons in an atom of selenium and the number electrons in an atom of Aluminium is 21;
The number of electrons in Aluminium is 13
Selenium is 34
Since the atoms are considered here, their atomic number, number of protons and number of electrons are the same.
It is only when we are considering ions that the number of electrons differ from the atomic number/ number of protons.
Difference = 34 - 13 = 21
We clearly see that selenium is 13 electrons more than aluminium.
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Answer:
ρ = 1.08 g/cm³
Explanation:
Step 1: Given data
Mass of the substance (m): 21.112 g
Volume of the substance (V): 19.5 cm³
Step 2: Calculate the density of the substance
The density (ρ) of a substance is equal to its mass divided by its volume.
ρ = m / V
ρ = 21.112 g / 19.5 cm³
ρ = 1.08 g/cm³
The density of the substance is 1.08 g/cm³.
<span>Oxygen, nitrogen, and fluorine bond with hydrogen to form molecules. These molecules are attracted to each other by...
hydrogen bonds. Hydrogen bonding is one of the strongest types of bonding in chemistry. A bond between hydrogen and oxygen, or hydrogen and nitrogen, or hydrogen and fluorine is required for molecules to have hydrogen bonds.</span>
Answer is: <span>the solubility of the new compound.
</span>Precipitates are insoluble ionic solid products, formed when certain cations and anions combine. Factors need for precipation reactions are: <span>temperature, buffers, solution concentration.</span>
Solubility rules determines if precipate will occur or not.
Answer:
Explanation:
The objective of this question is all about identifying the phenomena that holds true for the statement being said in each instance. Let; walk through them.
a) Whenever you see 9 or a multiple of 9 in the integration ratio, which group should you first consider for being responsible for that signal.
( C₄H₉ )Tert. Butyl group
b) Whenever you see a quartet and triplet on a spectrum, which group should you first consider for being responsible for those signals?
(CH₃CH₂) ethyl group
c) Whenever you see septet and a doublet on a spectrum, which group should you first consider for being responsible for those signals?
(CH(CH₃)₂) isoproply group
d) Whenever you see 6 or a multiple of 6 in the integration ratio, which group should you first consider for being responsible for that signal
(CH(CH₃)₂) isoproply group
e) Whenever you see 3 as the actual number of protons for a given signal, which group should you first consider for being responsible for that signal.
CH₃- methyl group
A perfect description showing the explanation of each answers chosen is explained with an aid of diagram below.