Answer:
Option B is correct.
Explanation:
An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. The number of protons or neutrons is the atomic number of an atom while sum of proton and neutrons is the mass number.
The beryllium atom have five neutrons, four protons and four electrons.
The option be is correct model of beryllium because it shows that there are four protons and five neutron in nucleus of beryllium atom and four electrons revolving around the nucleus.
Beryllium is alkaline earth metal.
It is present in group two.
Its atomic number is 4.
its atomic mass is 9 amu.
Answer:
Addition of a catalyst can speed up a reaction by providing an alternate reaction pathway that has a lower activation energy
Explanation:
A catalyst is an agent that increases the rate of a chemical reaction by providing an alternate pathway for the reaction that requires a lower activation energy. As the requirement for activation energy is less in the presence of a catalyst, there are more reactant particles becoming involved in the chemical reaction and as such there are more products formed per unit time, or there is an increase in the rate of the reaction
Example of catalyst include
1. Addition of potassium permanganate to hydrogen peroxide to aid in the rapid decomposition into water and oxygen
2. Platinum serves as a catalyst in the complete combustion of carbon monoxide into carbon dioxide.
The number of moles in 3.612 x 10²⁴ molecules of CaO is 6 moles.
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Number of moles in the molecules</h3>
The number of moles in 3.612 x 10²⁴ molecules of CaO is calculated as follows;
6.02 x 10²³ molecules = 1 mole
3.612 x 10²⁴ molecules = ?
= (3.612 x 10²⁴ ) / (6.02 x 10²³ )
= 6 moles
Thus, the number of moles in 3.612 x 10²⁴ molecules of CaO is 6 moles.
Learn more about number of moles here: brainly.com/question/15356425
Answer:
Number of moles of oxygen = 0.037 mol
Explanation:
Given data:
Total pressure = 98.5 KPa
Partial pressure of nitrogen = 22.0 KPa
Partial pressure of argon = 50.0 KPa
Volume = 3.5 L
Temperature = 25°C (25+273= 298K)
Number of moles of oxygen = ?
Solution:
Total pressure = P(N₂) + P(O₂) + P(Ar)
98.5 KPa = 22.0 KPa +P(O₂) + 50.0 KPa
98.5 KPa = 72.0 KPa +P(O₂)
P(O₂) = 98.5 KPa - 72.0 KPa
P(O₂) = 26.5 KPa
KPa to atm:
26.5 KPa/ 101 = 0.262 atm
Number of moles of oxygen:
PV = nRT
n = PV/RT
n = 0.262 atm × 3.5 L / 0.0821 atm.L/mol.K × 298 K
n = 0.917atm.L /24.47atm.L/ mol
n = 0.037 mol
Answer:
The pH decreases.
Explanation:
Hello,
In organic chemistry, oxidation accounts for either the increasing of C-O bonds or the increasing in the oxygen atoms into the molecule. Thus, if we consider the oxidation from benzyl alcohol to benzoic acid, there will be a carboxyl functional group instead of a hydroxile one. Now, the presence of the polar -O-H bonds that are ionizable, there will be a 
releasing causing the pH to decrease (increase acidity).
Regards.
