A balloon is inflated to a volume of 7.0 L 7.0 L on a day when the atmospheric pressure is 765 mmHg. The next day, as a storm front arrives, the atmospheric pressure drops to 737 mmHg 737 mmHg . Assuming the temperature remains constant, what is the new volume of the balloon, in liters?

The new volume is 7.27 L

Explanation:

Step 1: Data given

The initial volume of the balloon = 7.0 L

The pressure = 765 mmHg = 765/760 atm = 1.00658 atm

The pressure drops to 737 mmHg = 737/ 760 atm = 0.969737

The temperature remains constant

Step 2: Calculate the new volume

P1*V1 = P2*V2

⇒with P1 = the initial pressure in the balloon = 765 mmHg

⇒with V1 = the initial volume = 7.0L

⇒with P2 = the decreased pressure = 737 mmHg

⇒with V2 = the new volume = TO BE DETERMINED

765 mmHg * 7.0 L = 737 mmHG * V2

V2 = (765 mmHG * 7.0 L) / 737 mmHG

V2 = 7.27 L

The new volume is 7.27 L

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.