Molarity = 3.9 * 10 ^ -8
pH = - log (3.9 * 10 ^ -8)
pH = - (-7.40893539)
pH = 7.409 = 7.4 ... Ans
Answer:
i think it is the last option a pure substance that can be separated into different elements by chemical means
Explanation:
Volume = a x a x a
V = 2 cm x 3 cm x 4 cm => 24 cm³
Density = 19.3 g/cm³
Mass = ?
Therefore:
m = D x V
m = 19.3 x 24
m = 463.2 g
endothermic means it absorbs energy while exothermic means it releases energy. remember this.