Answer: (3) They have different masses and the same charges.
Explanation:
Atoms are mainly composed of three main types of particles (in fact there are more particles that are smaller and make up these main particles): electrons, protons and neutrons.
In the specific case of <u>electrons</u> and <u>protons</u>, <u>both have the same charge, but electrons have the opposite sign</u>. This means a proton has an electric charge of +1 and an electron has an electric charge of −1.
On the other hand, <u>protons have more mass than electrons.</u> In fact, thetex]mass of an electron is about approximately 
the mass of a proton, this means these negative charged particles contribute almost nothing to the total mass of an atom (unlike protons, which together with neutrons, make up virtually all of the mass of an atom).
However, each atom that is electrically neutral has the same quantity of electrons as protons.
The reaction formula of this is C3H8 + 5O2 --> 3CO2 + 4H2O. The ratio of mole number of C3H8 and O2 is 1:5. 0.025g equals to 0.025/44.1=0.00057 mole. So the mass of O2 is 0.00057*5*32=0.0912 g.
PbCr04 + P4O10
Hope this helps!
Answer:
Density of the He atom = 12.69 g/cm³
Explanation:
From the information given:
Since 1 mole of an atom = 6.022x 10²³ atoms)
1 atom of He = 
The volume can be determined as folows:
since the diameter of the He atom is approximately 0.10 nm
the radius of the He = 
= 0.05 nm
Converting it into cm, we have:
Assuming that it is a sphere, the volume of a sphere is
= 
= 
= 
Finally, the density can be calcuated by using the formula :
D = 12.69 g/cm³
Density of the He atom = 12.69 g/cm³
