Brainliestttme : )

fill in the boxes in the picture.

So for making the lewis structure, you have to remember that you put the most electronegative atom in the middle, or the closest to fluorine (F) on the periodic table. O is closer, so we put that in the middle. I attached the lewis structure because this one's too complicated to do in just text. We know because the H2 comes next to the carbon that it's connected to the carbon.

There's two electron unbonded pairs and two bonded pairs, so we have the bent structure. I've attached the VSPER sketch again.

This molecule is polar because there's an uneven sharing of electrons - the H atoms will be slightly positive because C is more electronegative and pulls the shared electrons toward it.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.