Answer: A
Explanation: the only way to turn it from blue to yellow is to mix it with an acidic solution.
Atomic mass iron ( Fe ) = 55.84 a.m.u
55.84 g ------------ 6.02x10²³ atoms
24.0 g ------------- ??
24.0 x ( 6.02x10²³) / 55.84
=> 2.58x10²³ atoms
Sunlight? air? i’m not sure they could all be matter..
Answer:
D. 0.75 grams
Explanation:
The data given on the iridium 182 are;
The half life of the iridium 182, 
= 15 years
The mass of the sample of iridium, N₀ = 3 grams
The amount left, N(t) after two half lives is given as follows;
For two half lives, t = 2 ×
∴ t = 2 × 15 = 30
∴ The amount left, N(t) = 0.75 grams
Answer:
No
Explanation:
Protons determine the type of element it is which the number of protons.
Isotopes are determined by the same elements with the same amount of protons, but different number of neutrons.
