<em>Answer:</em>
- The atom consist of three parts, proton, neutron and electrons. The electrons determine that i will combine or beak from other substances.
<em>Explanation:</em>
The atom consist of three parts which are following
The proton and neutron form nucleus of an atom. It is present at center of an atom. They have positive charges, while electrons remained outside the nucleus in particular energy levels or shell around the nucleus.
During combination or breaking of substances ,only arrangements of electrons take place. The valence shell electrons decide whether they have to combine or not, while nucleus remained unchanged during any reactions.
Answer:
1. get vitamin c
2. get your bone mineral density tested
3. don't smoke or drink excessively
4. start weight-bearing exercise
Explanation:
helps improve skeletal system
Answer: b) Doppler Effect
Explanation:
Line broadening in AAS, arises due to some effects, which can occur due to a number of factors. The line width broadening effects include: Doppler, Lorentz, Self absorption, and quenching effects.
Doppler effect arises because along the line of observation, atoms will have different components of velocity.
Answer: Lithium
Explanation: The balanced chemical equation is:

It can be seen, 4 moles of lithium combines with 1 mole of oxygen gas to produce 2 moles of lithium oxide.
Thus 8.4 moles of lithium combines with=
of oxygen gas to produce 4.2 moles of lithium oxide.
As, Lithium limits the formation of product, it is the limiting reagent and Oxygen gas is present in excess, it is called the excess reagent. (4.6-2.1)=2.5 moles of oxygen gas are present in excess.