Answer:
The last one, Positive charge occupies a very small volume in the atom.
Explanation:
Three signs that a chemical change has taken place is 1) color change 2) formation of gas bubbles 3) a change in temperature ( if you have ever bleached your hair the reason why it is warm to the touch is because of a chemical reaction)
Answer:
True
Explanation:
Electrons that are in the first energy level (energy level 1) are closest to the nucleus and will have the lowest energy. Electrons further away from the nucleus will have higher energy. An atom's electron shell can accommodate 2n2 electrons, where n is the energy level.
Answer:
The compound is N2O4
Explanation:
We have certain important pieces of information about the compound;
1) it is an oxide (a binary compound of nitrogen and oxygen)
2) there are no N-N bonds present
3) there are no O-O bonds present
Since it contains only nitrogen and oxygen then nitrogen accounts for 25.9% of the molecule by mass then oxygen should account for (100-25.9) = 74.1% oxygen
Relative atomic mass of oxygen = 16
Relative atomic mass of nitrogen = 14
We now deduce the empirical formula
Nitrogen. Oxygen
25.9/14. 74.1/16
1.85/1.85. 4.6/1.85 (divide through by the lowest ratio)
1 2
Empirical formula is NO2
To find the molecular formula
(NO2)n = 108
(14+2(16))n= 108
46n=108
n= 108/46
n= 2
Therefore molecular formula= N2O4