Answer:
320 g
Step-by-step explanation:
The half-life of Co-63 (5.3 yr) is the time it takes for half of it to decay.
After one half-life, half (50 %) of the original amount will remain.
After a second half-life, half of that amount (25 %) will remain, and so on.
We can construct a table as follows:
No. of Fraction Mass
half-lives t/yr Remaining Remaining/g
0 0 1
1 5.3 ½
2 10.6 ¼
3 15.9 ⅛ 40.0
4 21.2 ¹/₁₆
We see that 40.0 g remain after three half-lives.
This is one-eighth of the original mass.
The mass of the original sample was 8 × 40 g = 320 g
Answer:
5
Explanation:
all you do is the math expression
Answer:
(d) soap.
Explanation:
A soap is obtained by alkaline hydrolysis of a fat to yield the soap and glycerol. This process is known as saponification.
A soap solution is usually basic. Since phenolphthalein turns pink in an alkaline solution, then when phenolphthalein is added to a soap solution, the solution soon turns pink because it is alkaline in nature.
As a matter of fact, a soap sometimes has almost the pH of baking soda!
Answer:
The answer to your question is 21.45 g of KBr
Explanation:
Chemical reaction
2K + Br₂ ⇒ 2KBr
14.4 ?
Process
1.- Calculate the molecular mass of bromine and potassium bromide
Bromine = 2 x 79.9 = 159.8g
Potassium bromide = 2(79.9 + 39.1) = 238 g
2.- Solve it using proportions
159.8 g of Bromine ------------ 238 g of potassium bromide
14.4 g of Bromine ------------ x
x = (14.4 x 238) / 159.8
x = 3427.2 / 159.8
x = 21.45g of KBr
Answer:
I think it is covalent bonding...
Explanation:
The bonding is covalent in homonuclear diatomic molecules. Each atom in the molecule has the same electronegativity, which means electrons are shared equally between the two. The electronegativity of the atoms in heteronuclear diatomic molecules varies, and these molecules have polar covalent bonds. A dipole is formed when a molecule interacts with another molecule. (i think it's covalent bonding but i might be wrong)
hope this helps...