Answer:
1) When 6.97 grams of sodium(s) react with excess water(l), 56.0 kJ of energy are evolved.
2) When 10.4 grams of carbon monoxide(g) react with excess water(l), 1.04 kJ of energy are absorbed.
Explanation:
1) The following thermochemical equation is for the reaction of sodium(s) with water(l) to form sodium hydroxide(aq) and hydrogen(g).
2 Na(s) + 2H₂O(l) ⇒ 2NaOH(aq) + H₂(g) ΔH = -369 kJ
The enthalpy of the reaction is negative, which means that 369 kJ of energy are evolved per 2 moles of sodium. The energy evolved for 6.97 g of Na (molar mass 22.98 g/mol) is:

2) The following thermochemical equation is for the reaction of carbon monoxide(g) with water(l) to form carbon dioxide(g) and hydrogen(g).
CO(g) + H₂O(l) ⇒ CO₂(g) + H₂(g) ΔH = 2.80 kJ
The enthalpy of the reaction is positive, which means that 2.80 kJ of energy are absorbed per mole of carbon monoxide. The energy evolved for 10.4 g of CO (molar mass 28.01 g/mol) is:

Answer:
The options are not given, here are the options.
metal
a. Metal
b. a metalloid
c. a non-metal
d. a gas
The correct option is C.
Non metal
Explanation:
Henry should classify it as non metals because non metals are substances or elements that are poor conductors of heat and electricity they break easily I .e meaning they lack the ducibility of metals, meaning they cannot be stretched, they are brittle, they are not shiny and does not reflect light, they have high electronegativities that is they have atoms that can hold electrons to what they have.
If the cube is 3 cm on each side, then it has a volume of 27 cm^3 (3 x 3 x 3). Density is mass divided by volume, so its density is 72.9/27 = 2.7 g/cm^3.
<span>Going by the density, the cube is made of Aluminium - density is a fairly unique quantity</span>
Answer:
21.182 g
Explanation:
There are about (6.0)(10^23) atoms in one mole of a substance, so the given sample has about 0.333 mol of Cu.
The atomic mass of Cu is 63.546 g/mol, meaning that the answer is about <u>21.182</u><u> </u><u>g</u>
Answer:
In my opinion, water is a compound.
Explanation:
Water is mixed from Oxygen(O) and Hydrogen(H) and they cannot be splitted.
Sorry if there any mistakes