Noble gas. Noble gas, any of the seven chemical elements<span> that make up Group 18 (VIIIa) of the </span>periodic table<span>. The </span>elements<span> are </span>helium<span> (</span>He<span>), </span>neon<span> (</span>Ne<span>), argon (Ar), krypton (Kr), </span>xenon<span> (</span>Xe<span>), radon (Rn), and oganesson (Og)</span>
Answer:
There are 1000 mg in 1. g
There are 1000 g in 1 kg
Each students needs 2,250 mg of clay
Explanation:
In order to determine the amount of how many kilograms to order, the teacher will need to find out the total mass of clay required by the students and then the teacher will have to convert the total mass to the units required for the purchase.
The teacher would have to find out how many milligrams make one kilogram as follows
1 kg = 1000 g
1 g = 1000 mg
Therefore, 2,250 mg = 2250/1000 g = 2.25 g
2.25 g = 2.25/1000 kg = 0.00225 kg.
Answer:
<em>3.27·10²³ atoms of O</em>
Explanation:
To figure out the amount of oxygen atoms in this sample, we must first evaluate the sample.
The chemical formula for sodium sulfate is <em>Na₂SO₄, </em>and its molar mass is approximately 142.05
.
We will use stoichiometry to convert from our mass of <em>Na₂SO₄ </em>to moles of <em>Na₂SO₄</em>, and then from moles of <em>Na₂SO₄ </em>to moles of <em>O </em>using the mole ratio; then finally, we will convert from moles of <em>O </em>to atoms of <em>O </em>using Avogadro's constant.
19.3g <em>Na₂SO₄</em> · 
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After doing the math for this dimensional analysis, you should get a quantity of approximately <em>3.27·10²³ atoms of O</em>.
Answer:
Kr-81 is most stable because of its high half lige and kr-73 is the most radioactive because of its least half life
Explanation:
Stability is directly proportional to half life of a reaction
Mutation affect a species ability to survive and reproduce. Mutations can expand the life span of a species by keeping them hidden from predators which would also increase reproduction. If exposed to other wildlife, those numbers could decrease.
