The maximum number of electrons:
- s sublevel: 2 electrons,
- p sublevel: 6 electrons,
- d sublevel: 10 electrons,
- f sublevel : 14 electrons.
Gases
liquids
plasma
solids
condensates <span />
Answer:
Number of protons = 82
Explanation:
Given data:
Atomic number of Pb = 82
Mass number of Pb-207 = 207
Number of protons = ?
Solution:
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. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
Atomic number of Pb = number of protons or electrons
82 = number of protons or electrons
Mass number = Number of protons + number of neutron
207 = 82 + number of neutron
Number of neutrons = 207 - 82
Number of neutrons = 125
A elephant egg cell has 28 chromosomes.
Both elephant egg and sperm cell make a zygote with 56 chromosomes.
Answer:
Double replacement
Precipitation reaction
Explanation:
You have the reaction:
REACTANTS PRODUCTS
BaCl₂ (aq) + Na₂SO₄ (aq) ⇒ 2NaCl (aq) + BaSO₄(s)
The general form of a double replacement reaction is the following:
AB + CD ⇒ CD + AB
The reactants basically, exchanged partners. In the case of your problem, Barium(Ba) and Sodium(Na) switched places. So this makes it a double-replacement reaction.
Now how do I know it is a precipitation reaction. A precipitation reaction occurs when two solutions combine and salt is formed. Salt is solid, so how do I know that's what occured? Look at your equation again:
BaCl₂ (aq) + Na₂SO₄ (aq) ⇒ 2NaCl (aq) + BaSO₄(s)
aq means aqueous (liquid)
s means solid
If you look at the product formed in the reaction, from two solutions, it formed a solid. So this is your clue as to why it is a precipitation reaction.
