The two properties which are used to define matter are that it has mass
and it takes up space. The other properties do not necessarily apply to
each matter. Such some matter can be a conductor of heat (such as metal)
and some not (such as non metals). Likewise, some matter can be buoyant
and float on liquid of density more than it but others would not on the
liquids of density less than it. In-fact not all the matters are
conductors of energy (such as heat, sound, electricity) or at-least a
very poor conductor of energy and tend to find application as
insulating agents (non conductors). So the only thing which is
necessarily true is that the matter would definitely have mass in even
their minutest form as atom and would take up some space.
Answer:
1. Proton = 4
2. Neutron = 5
3. Electron = 2
Explanation:
9 4Be^2+
From the above, we obtained the following:
Atomic number = 4
Mass number = 9
Charge = +2
1. Determination of the proton.
Atomic number is simply defined as the proton number. This implies that:
Atomic number = proton number
Atomic number = 4
Therefore,
4 = proton number
Proton = 4
2. Determination of the Neutron.
Mass number = Proton + Neutron
Mass number = 9
Proton = 4
Neutron =?
Mass number = Proton + Neutron
9 = 4 + Neutron
Collect like terms
Neutron = 9 – 4
Neutron = 5
3. Determination of the electron.
From the question given
9 4Be^2+
The atom has a charge of +2. This implies that the atom has lose 2 electrons. Thus we can obtain the electron as follow:
Proton = 4
Charge = +2
Electron =?
Electron = Proton – charge
Electron = 4 – 2
Electron = 2
Answer:
The molar mass of the unknown gas is 
Explanation:
Let assume that the gas is O2 gas
O2 gas is to effuse through a porous barrier in time t₁ = 4.98 minutes.
Under the same conditions;
the same number of moles of an unknown gas requires time t₂ = 6.34 minutes to effuse through the same barrier.
From Graham's Law of Diffusion;
Graham's Law of Diffusion states that, at a constant temperature and pressure; the rate of diffusion of a gas is inversely proportional to the square root of its density.
i.e
where K = constant
If we compare the rate o diffusion of two gases;
Since the density of a gas d is proportional to its relative molecular mass M. Then;
Rate is the reciprocal of time ; i.e
Thus; replacing the value of R into the above previous equation;we have:
We can equally say:
This is so the rain drains off and dosent cause run off
Answer:
3. 2.00 L of air at 100°C has twice the pressure of the same 2.00 L of air at 50°C
Explanation:
1) doubling the pressure of a gas doubles its volume
This is incorrect because by increasing the pressure volume is going to be decreased.
2) 2.00 L of air at 227°C has twice the pressure of the same 2.00 L of air at 23°C
This is also incorrect because 2 L air at 227 °C will have the pressure more than twice time as compared to the 2L air at 23°C.
3. 2.00 L of air at 100°C has twice the pressure of the same 2.00 L of air at 50°C
This is correct;
According to Gay-Lussac Law,
The pressure of given amount of a gas is directly proportional to its temperature at constant volume and number of moles.
Mathematical relationship:
P₁/T₁ = P₂/T₂
thus, by increasing the temperature pressure is also goes to increase in the same ratio.
4. halving the pressure of a gas halves its volume
This is incorrect because halving the pressure of gas increasing its volume.
