Find the enthalpy change per mole of sodium when sodium reacts with water. 8 grams of sodium reacts with 227 cm3 of water, producing a temperature change from 298 K to 308.4 K. The specific heat capacity of water is 4.18 J/K g.

a chemical reaction happens

explanation:

what is the general relationship between a galaxy's distance from earth and its speed?

the answer is:

the farther away a galaxy is from us, the faster it is moving away from us.

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.  

a electronegativity decreases beacuse the size of nucleus is bigger.