Answer:

Explanation:
Assuming that all caculations are at normal pressure and -1.72°C :

Where
is the number of moles of hydrogen
is the mass of hydrogen
is the density of hydrogen
Answer: <u>Four</u>Explanation: Calcium Sulfide is an ionic compound made up of Ca²⁺ and S²⁻.
Ca²⁺ is formed as,
Ca → Ca²⁺ + 2 e⁻
These two electrons are accepte by Sulfur as,
S + 2 e⁻ → S²⁻
So, before accepting 2 electrons S was having six valence electrons, after accepting two electrons from Ca it has 8 electrons which are present in four pairs as shown below,
Answer:
<h2>isotope is a variants of a particular chemical element which differ in neutron number, and consequently in nucleon number.All isotopes of a given element have the same number of protons but different number of neutrons in each atom.</h2>
<h2>The 2 important physical properties of isotope is</h2>
<h2>1.<u>M</u><u>e</u><u>l</u><u>t</u><u>i</u><u>n</u><u>g</u><u> </u><u>Points</u></h2><h2>
2.<u>B</u><u>o</u><u>i</u><u>l</u><u>i</u><u>n</u><u>g</u><u> </u><u>Points</u></h2>
There are 30 inches in 2.5 just know that a foot is 12 inches so 12 times 2.5 is 30
Answer:
precipitation
Explanation:
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