The half-life of cobalt-60 is 5.26 years. After 10.52 years, 5 grams of a 20-gram sample will remain is TRUE
<u>Explanation:</u>
Mass of cobalt = 20 g
Half-life = 5.26 years
Mass remains after 10.52 years = 5 g
This can be solved by using given below formula, 
= initial mass
t = number of years from when the mass was m_0
m(t) = remaining mass after t years
Number of half-lives = 
Number of half-lives = 
Number of half-lives = 2
At time zero = 20 g
At first half-life =
= 10 g
At second half life =
= 5 g
The given statement is true.
Answer:
A) a chain reaction that is caused by nuclear fission
Answer:
When an atom loses electron(s) it will lose some of its negative charge and so becomes positively charged. A positive ion is formed where an atom has more protons than electrons. In the opposite case when an atom gains electron(s) it becomes negatively charged (more electrons than protons).
Explanation:
n=20 mol
(NH)4 SO4
Atomic masses :
N- 14
H- 1
S- 32
O- 16
Therefore M= 14×2 + 1×8 + 32 + 16×4
= 132
m= nM
= 20×132
= 2640g
<span>Fungal diseases are difficult to treat mainly because they are eukaryotic organisms just like us humans, and therefore have less differences for drugs to target without harming the human body as well. Most antibiotics target e.g. the peptidoglycan layer in the bacterial (a prokaryote) cell wall, which is a safe target since eukaryotic cells do not have equivalent structures. Similarly many differences in metabolic pathways between humans and prokaryotes is often targeted by antibiotics, but metabolism of fungi and humans is much more uniform, and hence it is difficult to exclusively target the fungi only.
HOPE THIS HELPS!
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