Looks like it would be A................
Answer:
1.2 cm³.
Explanation:
The following data were obtained from the question:
Mass of neckl = 40 g
Density of gold = 19.3 g/cm³
Volume of gold =..?
Next, we shall determine the mass of the gold in the necklace.
From the question given above, we were told that 58% of the mass of the necklace is gold. Thus, we can obtain the mass of the gold in the necklace as follow:
Mass of neckl = 40 g
Mass of gold =?
Mass of gold = 58% × 40
Mass of gold = 58/100 × 40
Mass of gold = 23.2 g
Therefore, the mass of the gold in the necklace is 23.2 g
Finally, we shall determine the volume of the gold in the necklace as follow:
Density of gold = 19.3 g/cm³
Mass of gold = 23.2 g
Volume of gold =..?
Density = mass /volume
19.3 = 23.2/Volume
Cross multiply
19.3 × Volume = 23.2
Divide both side by 19.3
Volume = 23.2 / 19.3
Volume of gold = 1.2 cm³
Therefore, the volume of the gold in the necklace is 1.2 cm³
Answer:
B.
Explanation:
There are the same amount of black circles in the reactant and product. There are also the same amount of white circles in the product and reactant.
In writing chemical reactions, it is important that you know the chemical formula of each substance and in balancing them, it should be that the number of each element in both side are equal.
2K(s) + 2H2O(l) = 2KOH(aq) + H2(g)
