Answer:
B. Halogen
Explanation:
Halogens are the family of chemical elements found in the group VIIA of the periodic table which means they possess seven (7) outer electrons. Some examples of halogens are Fluorine (F), Iodine (I), Bromine (Br), and Chlorine (Cl).
A halogen, or an element located in group 7A, will form a salt when reacted with a metal atom.
For example, when Chlorine reacts with Sodium it would form a salt known as Sodium Chloride.
Na + Cl ----> NaCl
The equilibrium means that amount that are coming equals the amount that are going.
So the correct answers are
<span>2. A person's income and expenses are equal every month.
</span><span>3. The pressure exerted on the inside of a balloon by the gas inside is equal to the pressure exerted on the outside of the balloon by the atmosphere.</span>
The statement about electronegativity that is correct is <span>D. Noble gases have the highest electronegativity values.</span>
Answer:
Through their adaptations from their habitat; environment
Explanation:
Charles Darwin explains evolution and their genetic material evolves during the process. For example, fruit birds have narrow bills whilst seed-eating birds have big bills. The foods they eat forced their DNA to adapt with the system in order to survive.
Answer:
20 amu
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. For example if neutral atom has 6 protons than it must have 6 electrons. 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 mass = Number of protons + number of neutrons
Atomic number = Number of electrons or number of protons.
In given question it is stated that atom has 11 electrons and -1 charge it means this atom has 12 electrons in neutral state.
Thus it has 12 protons because number of electrons and protons are always equal.
Atomic mass of given atom:
Atomic mass = Number of protons + number of neutrons
Atomic mass = 12 + 8 = 20 amu