Answer:
1. Nuts
2. Canned meats and seafood
3. Dried grains
4. Dark chocolate
5. Protein powders
The reaction is as follows:
2 H₂(g) + O₂(g) → 2 H₂O(g) . ΔH = - 483.5 kJ
Using the change in enthalpy and heat, calculate the moles as follows:
Moles of H₂ = -

x 2 mol H₂
= - 216 kJ / (-483.5 kJ) x 2 mol H₂
= 0.893 mol H₂
Calculate the mass of H₂ using the moles and molar mass as follows:
0.893 mol H₂ x (2.02 g H₂ / 1 mol H₂) = 1.79 g H₂
Therefore, the mass of hydrogen gas is 1.79 g
Answer;
-Not that reactive
The element found is not very reactive.
Explanation;
-If an element is found in nature in its pure elemental state then the the element found is not very reactive.
-There are many elements which are not much reactive. such as in metals- Ag, Au, Hg, Cu etc. and in Non metals- O2, N2, Inert gases etc.
-
For checking its chemical properties you will have to examine it with O2 or C-12.
The correct answer is option A and B
About 300 B.C., Aristarchus suggested that the sun was at the center of the universe because a) the brightness of the planets would change and b) the planets appeared to move among the constellations.
18 centuries before Copernicus, Aristarchus predicted that all planets orbit the sun. In other words, he suggested the Solar System is heliocentric.