Explanation:
when an iron bar rust is an example of a chemical change in which a new substance is formed and the change is not easily reversible.for iron to rust moisture and air must be present.while when a substance freezes,it can be easily reversed through melting and no new substance is formed.this change is termed a physical change.
<span>The number of moles of Cl- ions needed to combine completely with 0.25 mole of Mg+2 ions is:
0.50.</span>
Answer: 100kPa
Explanation:
P1 = 3.00 x 10² kPa , P2 =?
T1 = 30°C = 30 +273 = 303k
T2 = —172°C = —172 + 273 = 101k
P1/T1 = P2/T2
3 x 10² / 303 = P2 / 101
P2 = (3 x 10² / 303) x 101
P2 = 100kPa
Answer:
25.33125KPa
Explanation:
From the above,
1atm = 101.325KPa
0.25atm = (0.25atm x 101.325KPa) / 1atm = 25.33125KPa
Therefore, 0.25atm = 25.33125KPa
Answer:
Tea is a solution of compounds in water, so it is not chemically pure.
Explanation:
It is usually separated from tea leaves by filtration. B Because the composition of the solution is uniform throughout, it is a homogeneous mixture.
