<u>Answer:</u> The correct answer is 
<u>Explanation:</u>
We are given:
Moles of hydrogen gas = 4 moles
As, oxygen is given in excess. Thus, is considered as an excess reagent and hydrogen is considered as a limiting reagent because it limits the formation of products.
For the given chemical equation:
By Stoichiometry of the reaction:
2 moles of hydrogen produces 2 moles of water molecule.
So, 4 moles of hydrogen will produce = 
of water.
Hence, the correct answer is
The molecular model is physical model of the atomic system used to <span>represent </span>molecules and their processes. It is used to <span>understand </span>chemistry<span> and generating and testing </span>hypotheses and it is the m<span>ost commonly used explicit representation of atoms. </span>
Answer: A
The protons in the nucleus repel each other
Explanation:
the number of protons inside a nucleus increases the electrostatic repulsion between protons increase reducing the binding energy. Thus the electrostatic force determines the stability of a nuclear configuration
Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or solitary as in yew, Torreya, Ginkgo.
Answer:
<h2>Speed = 5.107 mile/hr</h2>
Explanation:
<h3>Given:</h3>
<u>distance</u> =50m = 0.0311 mile
<u>Time</u>= 21.93 seconds/3600 =0.00609 hour
<u>Speed</u><u>=</u>?
<h3>
Speed= Distance / Time </h3><h3>
= 0.0311 / 0.00609</h3><h3>
= 5.107 mile/hr</h3>
