Answer:
both magnesium and strontium have 2 valence electrons
Explanation:
potassium has 8 valence electrons, and nitrogen has 5.
The correct answer is <span>X–rays.
X-beams or X-rays are a kind of radiation called electromagnetic waves. X-beam imaging makes photos of within your body. The pictures demonstrate the parts of your body in various shades of high contrast. This is on account of various tissues retain diverse measures of radiation.
</span>
Answer:
The the recoil velocity of the hunter is 0.056 m/s in opposite direction of the bullet.
Explanation:
Given;
mass of bullet, m₁ = 4.2 g = 0.0042 kg
mass of hunter + gun = 72.5 kg
velocity of the bullet, u = 965 m/s
Momentum of the bullet when it was fired;
P = mv
P = 0.0042 x 965
P = 4.053 kg.m/s
Determine the recoil velocity of the hunter.
Total momentum = sum of the individual momenta
Total momentum = momentum of the bullet + momentum of the hunter
Apply the principle of conservation of momentum, sum of the momentum is equal to zero.

Therefore, the the recoil velocity of the hunter is 0.056 m/s in opposite direction of the bullet.
Answer:
D. Atoms with eight valence electrons usually do not gain or lose
electrons.
Explanation:
An atom can be defined as the smallest unit comprising of matter that forms all chemical elements. Thus, atoms are basically the building blocks of matters and as such defines the structure of a chemical element.
Generally, these atoms are typically made up of three distinct particles and these are protons, neutrons and electrons.
Valence electrons can be defined as the number of electrons present in the outermost shell of an atom. Valence electrons are used to determine whether an atom or group of elements found in a periodic table can bond with others. Thus, this property is typically used to determine the chemical properties of elements.
Based on the octet rule which states that atoms of chemical elements gain, lose or share electrons so as to have eight (8) electrons in their valence shell. Therefore, atoms of chemical elements bond in order to attain the electronic configuration of a noble gas i.e a full valence shell which comprises of eight (8) electrons.
This ultimately implies that, atoms with eight valence electrons usually do not gain or lose electrons because they're noble gas.