<h3>
<u>Answer:</u></h3>
<u>1 mole of a gas at STP occupies 22.4 L volume </u>
<u>Now the volume is given =78.4 therefore,</u>
<u>No. of moles of gas = 78.4 ÷ 22.4 = 3.5 moles</u>
<u>I hope it helps you~</u>
Answer:
Iron has 26 electrons. Potassium has 39 neutrons. Nickel has 28 protons.
Explanation:
Answer:
As a substance changes from a solid to a liquid to a gas, its molecules first the molecules are moving fast enough, they are able to "escape." They leave the surface of the liquid as gas molecules. Evaporation is not the only process that can change a substance from a liquid to a gas. The same change can occur through boiling.
Explanation:
Explanation:
Scientifically speaking, metals are naturally occurring chemical elements that are typically hard, lustrous, and good conductors of both heat and electricity. Examples include iron, gold, silver, copper, zinc, nickel, etc., but also elements we don't normally think of as metals.
Answer : Hypothesis.
Explanation : Hypothesis is defined as the supposition or proposed explanation which can be made on the basis of limited available evidence as a starting point for further investigation. Here, in this question the proposed explanation for the changing colors of the sky is an example of a hypothesis.
A hypothesis has to be supported with scientific experiments which are reproducible by several experiments and test results have to be valid to be called as a scientific theory.
