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wariber [46]
3 years ago
13

When someone’s immune system overreacts to something harmless it’s called:

Chemistry
2 answers:
ruslelena [56]3 years ago
5 0
I feel like it would be c
Mama L [17]3 years ago
3 0
The answer to this question is C. An allergy.
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An alcohol is 58.80 % C and 9.889 % H by mass. The rest is oxygen. What is the empirical formula of the alcohol? Enter the eleme
PilotLPTM [1.2K]

Answer:

hco I believe

Explanation:

Pretty sure about this, when do you need to put it in?

6 0
3 years ago
Definition of biogenesis
Kay [80]

Answer:

Biogenesis is the production of new living organisms. Conceptually, biogenesis sometimes attributed to Louis Pasteur and encompasses the belief that complex living things come only from other living things, by means of reproduction.

Explanation:

8 0
3 years ago
Read 2 more answers
The half-life of radium-226 is 1590 years. if a sample contains 100 mg, how many mg will remain after 1000 years?
AlladinOne [14]

Answer:

64.52 mg.

Explanation:

The following data were obtained from the question:

Half life (t½) = 1590 years

Initial amount (N₀) = 100 mg

Time (t) = 1000 years.

Final amount (N) =.?

Next, we shall determine the rate constant (K).

This is illustrated below:

Half life (t½) = 1590 years

Rate/decay constant (K) =?

K = 0.693 / t½

K = 0.693/1590

K = 4.36×10¯⁴ / year.

Finally, we shall determine the amount that will remain after 1000 years as follow:

Half life (t½) = 1590 years

Initial amount (N₀) = 100 mg

Time (t) = 1000 years.

Rate constant = 4.36×10¯⁴ / year.

Final amount (N) =.?

Log (N₀/N) = kt/2.3

Log (100/N) = 4.36×10¯⁴ × 1000/2.3

Log (100/N) = 0.436/2.3

Log (100/N) = 0.1896

Take the antilog

100/N = antilog (0.1896)

100/N = 1.55

Cross multiply

N x 1.55 = 100

Divide both side by 1.55

N = 100/1.55

N = 64.52 mg

Therefore, the amount that remained after 1000 years is 64.52 mg

7 0
3 years ago
7. In which environment would liverworts and hornworts grow?
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5 0
3 years ago
Covalent bonded atoms make up what
White raven [17]
In a covalent bond, the atoms bond by sharing electrons. Covalent bonds usually occur between nonmetals. For example, in water (H2O) each hydrogen (H) and oxygen (O) share a pair of electrons to make a molecule of two hydrogen atoms single bonded to a single oxygen atom.
7 0
2 years ago
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