Answer:
The correct option is: stable environment
Explanation:
According to the Darwin's theory, natural selection is the concept by which all the small useful variations of traits are preserved.
According to Darwin, there are three <u>necessary and sufficient conditions</u> for the occurrence of natural selection:
1. struggle for existence
2. variation
3. inheritance
These conditions are said to be necessary because if these conditions are not satisfied then natural selection does not occur.
These conditions are said to be sufficient because if these conditions are satisfied, then natural selection will most definitely occur.
Answer:
Losing 2 valence electrons
Gaining 2 electrons
Answer:
Moment=Force x Pivot
Explanation:
A moment is the turning effect of a force. Moments act about a point in a clockwise or anticlockwise direction.
Law of moments:
When an object is balanced (in equilibrium) the sum of the clockwise moments is equal to the sum of the anticlockwise moments.
How to calculate moments:
Moment=Force x Pivot
Answer:
The answer to your question is letter C.
Explanation:
Reaction
Potassium hydroxide = KOH
Barium chloride = BaCl₂
Potassium chloride = KCl
Barium hydroxide = Ba(OH)₂
KOH + BaCl₂ ⇒ KCl + Ba(OH)₂
Reactant Elements Products
1 K 1
1 Ba 1
2 Cl 1
1 H 2
1 O 2
The reaction is unbalanced
2KOH + BaCl₂ ⇒ 2KCl + Ba(OH)₂
Reactant Elements Products
2 K 2
1 Ba 1
2 Cl 2
2 H 2
2 O 2
Now, the reaction is balanced
Answer:
The proton remains the same.
Explanation:
Oxidation is simply defined as the loss of electron(s) during a chemical reaction either by an atom, molecule or ion.
Oxidation is strictly on the transfer of electron(s) and not proton.
A metal that undergoes oxidation still has its protons intact otherwise it will not be called the ion of the metal since atomic number is called the proton number.
Sodium (Na) undergoes oxidation as follow:
Na —> Na+ + e-
Na is called sodium metal.
Na+ is called sodium ion.
Na has 11 electrons and 11 protons
Na+ has 10 electrons and 11 protons
From the above illustration, we can see that the protons of Na and Na+ are the same why their electrons differ because Na+ indicates that 1 electron has been loss or transferred.
