Answer: Option (c) is the correct answer.
Explanation:
A hydrogen bond is defined as a weak bond that is formed between an electropositive atom (generally hydrogen atom) and an electronegative atom like oxygen, nitrogen and fluorine.
An ionic bond is defined as a bond formed between a metal and a non-metal and in this bond transfer of electron takes place from metal to non-metal. And, due to the presence of opposite charges on the combining atoms there exists a strong force of attraction.
Vander waal forces are defined as the weak electric forces which tend to attract neutral molecules towards each other in gases, liquefied and solidified gases.
Vander waal forces are very weak forces.
Thus, we can conclude that Van der walas interactions are weak interactions would require the least amount of energy to disrupt.
I believe it is A because the plant is offering protection while the bacteria is converting it in to nitrogen that the plant can use!
Answer:
1)Na2O
let the valency of Na is x
2(x)+(2)=0
2x+2=0
2x=-2
x=-1
2)ZnO
let the valency of Zn is x
x+2=0
x=-2
3)Al2O3
let the valency of Al is x
2(x)+3(2)=0
2x+6=0
2x=-6
x=-3
4)MgO
let the valency of Mg is x
x+2=0
x=-2
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
Nothing unless it was dug out from roots if not they would grom back in a long period of time
