Answer:
A chemical change because a temperature change occurred, the solid disappeared and a gas was produces
Explanation:
Magnesium reacts with hydrochloric acid releasing energy, and leading to the formation of magnesium chloride and hydrogen gas. This is represented by the equation below:
Mg₍s₎ + 2HCl₍aq)⇒ MgCl₂₍aq₎ + H₂₍g₎
Answer:
Diluted concentration is 0.5M
Explanation:
Let's solve this with rules of three, although there is a formula to see it easier
In 1000 mL (1L), we have 2 moles of NaOH
In 250 mL we must have (250 . 2) / 1000 = 0.5 moles of NaOH
These moles will be also in 1 L of the final volume of the diluted solution
More easy:
1 L of solution has 0.5 moles of NaOH
Then, molarity is 0.5 M
The formula is: Concentrated M . Conc. volume = Diluted M . Diluted volume
2 M . 0.250L = 1L . Diluted M
0.5M = Diluted M
a resource that cannot be replenished in a short period of time