Answer:
a. The student performed the splint test incorrectly. He should of observed a popping sound when the splint was placed in the test tube.
Explanation:
It is given that a student performed an experiment where he dropped a nickel metal in to HCl solution. He observed the reaction and performed a splint test in the test tube that is filled with a gas which is formed while Nickle is dropped into the solution of HCl.
But the experiment that the student performed was incorrect. He must have observed the popping sound when the splint was placed in the test tube.
When the splint was added to the gas splint flared up. The hydrogen gas pops out when exposed to the flame.
Thus the correct option is (a).
Answer:
Project scope statement?
Explanation:
it's good one just do research on it
Answer:
- <em><u>Step 2 (the slow step).</u></em>
Explanation:
The rate-determining step is always the slow step of a mechanism.
That is so, because it is the slow step which limits the reaction.
Imaging that for assembling a toy you have process of three steps:
- 1. order ten pieces, which you can do in 1 minute: meaning that you can order order the pieces for 60/1 = 60 toys in 1 hour.
- 2. glue the pieces and hold the toy until the glue hardens, which takes 1 hour: meaning finishingh 1 toy in 1 hour.
- 3. pack the toy, which takes 2 minutes: meaning that you can pack 60/2 = 30 toys in one hour.
The time to glue and hold one toy until the glue hardens determines that you can assemble 1 toy in 1 hour and not 60 toys or 30 toys.
Thus, the step that determines the rate at which the reaction happens is the slowest step: step 2.
The correct answer is (D)
All the above are reasons the carbon , oxygen, and nitrogen cycles are vital to life on earth.
The explanation:
because :
1) Carbon, oxygen, and nitrogen are vital components of life on Earth.
2) The carbon, oxygen, and nitrogen cycles allow vital elements to return to usable form by organisms.
3)The carbon, oxygen, and nitrogen cycles are an important interface between biotic and abiotic factors
4) They are all biogeochemical cycles.
5) They all involve an interaction between living and nonliving elements.
6)They are all part of the Earth system.
The balanced chemical equation for the production of chromium metal from the reaction of chromium(ll) nitrate reacts with a strip of zinc is:
3 Zn + 2 Cr(NO₃)₃ → 2 Cr + 3 Zn(NO₃)₂
This is a redox reaction, which <u>is a chemical reaction in which one or more electrons are transferred between the reagents</u>, causing a change in their oxidation states. In the proposed reaction, Cr oxidation state goes from +3 to 0, becoming metallic chromium, while Zn goes from being Zn⁰ to Zn²⁺.
<u>The mass of chromium metal produced in the above reaction will be,</u>
425.0 mL x 
x 
x 
x 
= 5.52 g
So, the mass of chromium metal produced when 425.0mL of 0.25M chromium(ll) nitrate reacts with a strip of zinc that remains in excess is 5.52 g of Cr.
