Chlorine (Cl) forms a salt when it is combined with a metal. This element belongs in halogens. GROUP 17
Answer:An atom
Explanation:
Because molecules more spread out and have things that connnect them and are not bunched up togoether
And Atoms are all packed up like in the picture
Hope this helps!:D
Explanation:
Molar mass of HBr = 81 g/mol
Molar mass of nitrogen dioxide gas = 46 g/mol
Molar mass of ethane = 30 g/mol
Graham's Law states that the rate of effusion or diffusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows the equation:

So, the gas with least molar mass will effuse out fastest from the container and that is ethane gas.
The formula for average kinetic energy is:

where,
k = Boltzmann’s constant = 
T = temperature = 273.15 K ( at STP)
As we can see from the formula that kinetic energy depends upon only temperature of the gas molecule.
So, from this we can say that all the gas molecules have the same average kinetic energy at this temperature.
Answer:
Protons are positively charged. When a nucleus emits an alpha particle, these changes happen: the mass number decreases by 4. the atomic number decreases by 2.
Explanation:
The substance doesn't have a specific name. We just say that that substance is being reduced. Remember this mnemonic - OILRIG where "Oxidation is Loss, Reduction is Gain" of electrons.