Answer:Hydrogen is placed such because it exhibits some similar characteristics of both group1 and group VII elements.
Explanation:
The reason why hydrogen is similar to group 1 metals:
#It has same valence electron and inorder achieve octet state it can lose that electron and forms H+ ion
#It acts as a good reducing agent similar to group1 metals
#It can also halides
Similarity to halogens:
#hydrogen can also gain one electron to gain noble gas configuration. It can combine with other non metals to form molecules with covalent bonding.
#It exists as diatomin molecule,H2
#Have the same electronegativity nature
#its reaction with other metal
C. the expansion of the universe is accelerating
This question is hard but I found the answer from merit nation
Answer is: volume will be 3.97 liters.
Boyle's Law: the pressure volume law - volume of a given amount of gas held varies inversely with the applied pressure when the temperature and mass are constant.
p₁V₁ = p₂V₂.
p₁ = 755 torr.
V₁ = 5.00 l.
p₂ = 1.25 atm · 760 torr/atm.
p₂ = 950 torr.
755 torr · 5 l = 950 torr · V₂.
V₂ = 755 torr · 5 l / 950 torr.
V₂ = 3.97 l.
When pressure goes up, volume goes down.
When volume goes up, pressure goes down.
<u>The troposphere: </u>
H. This layer can have thunderstorms or clear, sunny skies.
A. The biosphere interacts most with this layer.
<u>The stratosphere:</u>
B. It is the second layer from Earth's surface.
G. Winds are strong and steady in this layer.
<u>The mesosphere:</u>
E. It is heated by the ozone layer beneath it.
D. This layer is where most meteor showers occur.
<u>The thermosphere :</u>
F. It contains the ionosphere and exosphere.
C. It contains layers of single, unmixed gas.
<u>Explanation:</u>
Depending on the Earth's temperature the atmosphere can be separated into layers. The troposphere, the stratosphere, the mesosphere and the thermosphere are those layers. The lowest layer is named as Troposphere (0-10 km from the Earth outer surface), it comprises about 75% of the atmosphere's total air and nearly most the water vapor.
Stratosphere (10-30) includes much of the surface ozone. The change in height temperature arises as this ozone absorbs ultraviolet (UV) radiation from the sun. The temperature in Mesosphere (30-50 Km) declines again with height, hitting a minimum of about -90 ° C at the "mesopause." Above this thermosphere (50-400 Km) is settled which is a area where temperatures rise with height once again. The penetration of intense UV and X-ray radiation from the sun induces this temperature rise.
