Answer:
Like most other metals, Gallium is solid at room temperature (or liquid if it is too hot in your room). But, if it is held [in hands] for long enough, it melts in your hands, and doesn't poison you like Mercury would. This is because of its unusually low melting point of (~29 degree Centigrade).
- It melts once it reaches its melting point.
:)
Answer:
H2 > N2 > Ar > CO2
Explanation:
Graham's law explains why some gases efuse faster than others. This is due to the difference i their molar mass. Generally; The rate of effusion of gaseous substances is inversely proportional to the square rot of its molar mass.
This means gases with low molar masses would have higher efusion rate compared to gases with higher molar masses.
So now we just need to compare the molar masses of the various gases;
Ar - 39.95
CO2 - 44.01
H2 - 2
N2 - 28.01
To obtain the order in increasing rate, we have to order the gases in decreasing molar mass. This order of increasing rate is given as;
H2 > N2 > Ar > CO2
There are several things that can help scientists evaluate which category something belongs to. The similarity in features is one of them. If two skulls looked alike, they were probably species of the same evolutionary category. For example say humans and monkeys rather than humans and dogs.
Similarly fossils have helped scientists categorise species. Study of the chromosomes (in cases with available chromosomes) can help scientists figure out a lot about the subjects and categorise them.
Explanation:
The emission of a beta particle is the result of the rearrangement of the unstable nucleus of the radioactive atom in order to acquire stability. For that, a phenomenon occurs in the nucleus, in which a neutron decomposes giving rise to three new particles: a proton, an electron (β particle), and a neutrino. The antineutrino and electron are emitted. The proton, however, remains in the nucleus.
The symbol is used to represent beta particles.
Answer: b. Beta
Answer:
Specific gravity of the sample = 8.947
Explanation:
Specific gravity of a substance is defined as the density of that substance divided by the density of water.
Density of water = 1000g/l
Density of substance = mass/volume
= 85/9.5 x 10^-3
= 8947.37 g/l
SG = 8947.37/1000
= 8.947
