Answer:
endothermic reaction
Explanation:
It simply means that you are witnessing<u> an endothermic reaction</u>.
An endothermic reaction is one that absorbs heat energy from its surrounding, thereby leaving the reaction vessel with a lower temperature as compared to before the reaction.
It is as opposed to exothermic reactions which are reactions that give off energy in the form of heat to the surrounding, thereby leaving a reaction vessel warmer than before the reaction.
<em>In this case, the formation of ice crystals outside the test tube means that heat energy has been absorbed by the reaction which leaves the vessel a temperature cold enough to activate the formation of ice. </em>
Answer:
21 g of N₂ are produced by the decomposition
Explanation:
The reaction is: 2 NaN3 → 2 Na + 3 N2
2 moles of sodium nitride decompose in order to produce 2 moles of Na and 3 moles of nitrogen gas.
According to stoichiometry, ratio is 2:3. Therefore we say,
2 moles of nitride can produce 3 moles of N₂
Then, 0.5 moles of NaN₃ will produce (0.5 . 3) / 2 = 0.75 moles of N₂
We convert the moles to mass, to find the answer
0.75 mol . 28 g / 1 mol = 21 g
Ammonia and table salt dissolves in polar solvents, so A is water,
CO2 and hexane are non-polar substances, so they are going to be dissolved in non-polar solvent, so I think it is going to be carbon tetrachloride
Answer is <span>A) A - water; B - carbon tetrachloride
Table salt does not dissolve in oil and CCl4, and Br2 is too active and it is going to react with NH3.</span>
Explanation:
As we know that sum of only total number of protons are also known as atomic number of an atom. And, the sum of total number of protons and neutrons is known as atomic mass of an atom.
Number of protons help in determining the identity of an atom whereas the number of neutrons can be same for two or more number of atoms. But the number of protons will remain the same for a particular atom and for its isotopes.
For example, tex]^{1}_{1}H[/tex] and 
are isotopes and each of them contains 1 proton.
thus, we can conclude that the number of protons in their nuclei would allow you to determine whether two atoms are of the same or different elements.
