Answer:
97 000 g Na
Explanation:
The absortion (or liberation) of energy in form of heat is expressed by:
q=m*Cp*ΔT
The information we have:
q=1.30MJ= 1.30*10^6 J
ΔT = 10.0°C = 10.0 K (ΔT is the same in °C than in K)
Cp=30.8 J/(K mol Na)
If you notice, the Cp in the question is in relation with mol of Na. Before using the q equation, we can find the Cp in relation to the grams of Na.
To do so, we use the molar mass of Na= 22.99g/mol

Now, we are able to solve for m:
=97 000 g Na
I have no idea honestly I don’t remember I had it and I forgot it
Ionic bond is a type of chemical bond that refers to the bonding of <span>oppositely charged ions (anions and cations) because of attraction and the </span>transfer of valence electron(s) between atoms. Cation is the metal that loses electrons and become a positively charged cation, and anions are
the nonmetal that accepts those electrons to become a negatively charged
anion.
According this explanation, an ionic bond is:
B. the force that holds the valence electrons to the atom
Because it's protected from air because air makes it turn brown.
We have get the mass of gaseous water after evaporation in a closed container.
The mass of water vapor after evaporation is 5 grams.
In closed container, there is no exchange in mass from system to surrounding, only heat may exchange. The number of moles of water vapour remains unchanged as 5 gram water is heated in closed container.
Due to heating, liquid water gets evaporated and intermolecular distance between water molecules increases in gaseous state than liquid state and intermolecuar force of attraction decreases.
Randomness of molecules increases in gaseous state than liquid state.