Answer:
4, 16,
Explanation:
SI2 is sulphur diiodide. Sulphur is in group sixteen (six valence electrons) while iodine is in group 17(seven valence electrons).
Since there are two iodine atoms and one sulphur atom, the molecule has twenty valence electrons. Out of these twenty valence electrons, only four are bonding electrons. The other sixteen electrons include the four nonbonding electrons found on sulphur and the twelve non bonding electrons found on the two iodine atoms having six nonbonding electrons each.
If the angle is either 0 or 180, that means that there is either negative or positive work, so A and D are not correct.
If the angle is 45, then there is still some work involved.
The only option where there is no work done by a force is B. when the angle is between the force and displacement is 90.
Answer:
See Explanation
Explanation:
10) From the options provided for this question, gamma particle is the most energetic. Recall that gamma rays are high energy electromagnetic radiation which are capable of causing a high degree of ionization in matter.
11) The bombardment of U-235 with neutrons leads to the reaction;

Hence
a = 92, b= 95, c= 53
12) In positron emission, a proton is transformed into a neutron. The mass number of the daughter nucleus is the same as its parent but the atomic number decreases by 1.
Hence;

25.9 kJ/mol. (3 sig. fig. as in the heat capacity.)
<h3>Explanation</h3>
The process:
.
How many moles of this process?
Relative atomic mass from a modern periodic table:
- K: 39.098;
- N: 14.007;
- O: 15.999.
Molar mass of
:
.
Number of moles of the process = Number of moles of
dissolved:
.
What's the enthalpy change of this process?
for
. By convention, the enthalpy change
measures the energy change for each mole of a process.
.
The heat capacity is the least accurate number in these calculation. It comes with three significant figures. As a result, round the final result to three significant figures. However, make sure you keep at least one additional figure to minimize the risk of rounding errors during the calculation.
Answer:
Pb(NO3)2 + KI = KNO3 + PbI2