Answer:
Covalent bonds are formed when electrons are shared between elements that are nonmetals. The ammonium ion, NH+4 , would have covalent bonds because both nitrogen and hydrogen are nonmetals. ... The rest of the bonds all contain electrons from both hydrogen and nitrogen, so they would be considered ordinary covalent bonds.
The correct option is D.
Engineers and constructions workers have different types of footwear, which they make use of when they are in the field. Each of these foot wears has its own purpose and functions. For instance, the steel toe boots serve to protect the foot from falling falling objects and also from compression. The foot wear has a protective support in the toe and also possesses a mid sole plate to protect the foot again puncture from the sole.
Answer:
The experiment that did not give the results described is e) The Rutherford experiment proved the Thomson "plum-pudding" model of the atom to be essentially correct.
Explanation:
- First of all, let's start with the experiment listed in <em>b) The Rutherford experiment was useful in determining the nuclear charge on the atom</em>. This is true, because Rutherford was able to tell through this experiment that the atoms consisted mostly of empty space, with a positively charged nucleus in its center (he was able to tell it was positive because of the deflections observed on the positive alpha particles he used).
- Next, we have experiment <em>c) The electric discharge tube proved that electrons have a negative charge</em>. This is also true, given that Thomson was able to correctly determine that there existed particles that were negatively charged, called electrons (he determined this by observing that the rays deviated from the negatively charged plate of the discharge tube in his experiment).
- Experiment d) <em>Milikan's oil-drop experiment showed that the charge on any particle was a simple multiple of the charge on the electron</em>, also states the correct results. He was able to determine the charge of many electrically charged droplets of oil, and found out that the charges were a simple multiple of a base value, which he proposed to be that of the negative charge of an electron.
- Finally, we take a look at experiment <em>e) The Rutherford experiment proved the Thomson "plum-pudding" model of the atom to be essentially correct</em>. This is the experiment that did not give the result described. In fact, the Rutherford experiment proved that Thomson's "plum-pudding" model was not correct. This is because he determined that atoms consist mostly of empty space, with a dense, positively charged nucleus in its center, surrounded by negatively charged electrons. If Thomson's model were true, Rutherford would have not observed deflected alpha particles in his experiment.
Answer:
1) It is the number of particles in one mole of substance. It is an arbitrary definition to denote an amount of substance, not by its weight but by its number of molecules. Why? because that is convenient when doing certain calculations involving molecule formulas.
2) 1 mole of substance contains exactly as many particles as there are atoms in 12 grams of carbon-12.
3) The unified atomic mass unit is 1/12 of the mass of 1 carbon-12 atom.
So you see all three concepts are linked together.
