When two magnets are brought near each other, like poles repel; opposite poles attract. When a magnet is brought near a piece of iron, the iron also gets attracted to the magnet, and it acquires the same ability to attract other pieces of iron.
M=70.0 g
p=0.70 g/mL
v=m/p
v=70.0/0.70=100.00 mL
<h2> The correct option is (a).</h2>
Explanation:
- There is no change of state in pouring water into a vacuum insulated bottle as the vacuum created inside the bottle only reduces the time limit for the transfer of heat by conduction and convection.
- It helps the content filled in the bottle to be hot and cool for a longer time.
Hence, option (a) is correct.
Rest of the options (b), (c), (d), (e) is not correct because of the following reasons:
- In the sublimation of dry ice, the dry ice (solid-state) is changed to the vapour form.
- In the freezing of water, the liquid state is changed to solid-state.
- During the vaporization of alcohol, the liquid state is changed to the vapour form.
- During the melting of ice, the solid-state is changed to the liquid state.
Answer:
1. Alkali metals (group 1)
2. halogens (Group 17)
3. noble gasses (group 18)
Explanation:
1. alkali metals only have one valence electron meaning that they really want to lose that one valence electron to get a full octet.
2. halogens have 7 valence electrons meaning that they just need to gain 1 to get a full octet.
3. Nobel gasses already have a full octet meaning that they don't want to react. (atoms only react to get a full octet)
I hope this helps. Let me know if anything is unclear.
<span>The average molar bond enthalpy of the carbon-hydrogen bond in a CH4 molecule is 416 KJ/mol.
(+716.7 + (4 x 218) - (- 74.6) ) / 4
= + 1663.3 / 4
= 416</span>
