Answer:
Scientific laws or laws of science are statements, based on repeated experiments or observations, that describe or predict a range of natural phenomena. The term law has diverse usage in many cases across all fields of natural science.
Explanation:
I hope this helps
First find the oxidation states of the various atoms:
<span>in Cr2O2 2- Cr @ +1; In NH3 N @ +3; in CrO3 Cr @ +3, N2 N @ 0 </span>
<span>Note that N gained electrons, ie, was reduced; Cr was oxidized </span>
<span>Now there is a problem, because B has NH4+ which the problem did not, and is not balanced, showing e- in/out </span>
<span>B.NH4+ → N2 </span>
<span>Which of the following is an oxidation half-reaction? </span>
<span>A.Sn 2+ →Sn 4+ + 2e- </span>
<span>Sn lost electrons so it got oxidized</span>
Answer: -
The approximate number of atoms in a bacterium is 10¹¹
Explanation: -
We are given the mass of a bacterium is 10⁻¹⁵ kg.
We are told that the mass of a hydrogen atom is 10⁻²⁷ kg.
Finally we learn that the average mass of an atom of the bacterium is ten times the mass of a hydrogen atom.
Mass of an atom of bacterium = 10 x mass of hydrogen atom
= 10 x 10⁻²⁷ kg.
= 10⁻²⁶ kg.
Thus the number of atoms in a bacterium = 
= 
= 10¹¹
Answer:
Step 1 H2 + 2 NO → N2O + H2O (slow)
step 2 N2O + H2 → N2 + H2O (fast)
Explanation:
It is known that the slowest step in a reaction is the rate determining step in a sequence of reactions (reaction mechanism).
We have two important pieces of information in the question to guide our decision making process.
The overall reaction equation, and the rate expression. The two;
2 H2 + 2 NO → N2 + 2 H2O and rate = k[H2][NO]2 all support the answer given above.
I think the answer is B . I really hope that this helps you out.
