I believe B is your answer.
Hope this helps!
Answer: the density of the solid metal is 22.5176 g/cm
Explanation:
Given that;
mass of solid metal = 255 g
the cylinder and its contents weigh 101g less than before
also given that density of mercury = 13.6 g/cm³
Volume of the solid metal = volume of mercury which was absent in the first weighing
so let volume = Vcm³
Mass of mercury which was absent in the first weighing = density × volume
= 13.6 g/cm³ × Vcm³ = 13.6V g
now since the cylinder and its contents weigh 101g less than before,
it means the difference in mass between the solid and metal and the mass of mercury is equal to 101 g
so
255 - 13.6V g = 101g
13.6V g = 255 g - 101 g
13.6V = 154
V = 154 / 13.6
V = 11.3245 cm³
Now Density of solid metal will be;
⇒ mass / volume
= 255 / 11.3245
= 22.5176 g/cm
Therefore, the density of the solid metal is 22.5176 g/cm
Answer:
4.66 x 10^8 yr
Explanation:
The age of the rock can be calculated using the equation:
ln (N/N₀) = - kt where N is the quantiy of radioisotope decayed and N₀ is the initially quantity present of the radioisotope; k is the decay constant, and t is the time.
Now from the data , we have 78 argon-40 atoms for every 22 potassium-40 atoms, we can deduce that originally we had 22 + 78 = 100 atoms of potassium-40 so this is our N₀.
When we look at the equation, we see that k is unknown, but we can calculate it from the half-life which is given by the equation:
k = 0.693/ t half-life = 0.693/ 1.3 x 10⁹ yr = 5.33 x 10⁻¹⁰ yr⁻¹
Now we are in position to answer the question.
ln ( 78/100 ) = - (5.33 x 10⁻¹⁰ yr⁻¹ ) t
- 0.249 = - 5.33 x 10⁻¹⁰ yr⁻¹ t
0.249/ 5.33 x 10⁻¹⁰ yr⁻¹ = t
4.66 x 10^8 yr
Acids react with most metals to form a salt and hydrogen gas. ... For example, zinc metal reacts with hydrochloric acid producing zinc chloride and hydrogen gas. \[\ce{Zn(s) + 2HCl(aq) → ZnCl2(aq) + H2(g)}\] Bases react with certain metals like zinc or aluminum for example to also produce hydrogen gas.
