Answer:
The two observations we made from viewing the solar system model are as follows as:
1). When we look at the sky we observe that the motions of all the planets and the stars are perfect circular movements with a good and high speed, but not in velocity because in velocity direction doesn't charges.
2). The sun is at the centre of our solar system and all the planets are equidistant to each other planets and also revolve around the sun.
Answer:
41.3kJ of heat is absorbed
Explanation:
Based in the reaction:
Fe₃O₄(s) + 4H₂(g) → 3Fe(s) + 4H₂O(g) ΔH = 151kJ
<em>1 mole of Fe3O4 reacts with 4 moles of H₂, 151kJ are absorbed.</em>
63.4g of Fe₃O₄ (Molar mass: 231.533g/mol) are:
63.4g Fe₃O₄ × (1mol / 231.533g) = <em>0.274moles of Fe₃O₄</em>
These are the moles of Fe₃O₄ that react. As 1 mole of Fe₃O₄ in reaction absorb 151kJ, 0.274moles absorb:
0.274moles of Fe₃O₄ × (151kJ / 1 mole Fe₃O₄) =
<h3>41.3kJ of heat is absorbed</h3>
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The answer is c hopefully I helped you
Heat energy can be calculated by using the specific heat of a substance multiplying it to the mass of the sample and the change in temperature. It is expressed as:
<span>Energy = mCΔT
</span><span>Energy = 59.7 (0.231) (100-25)
</span><span>Energy = 1034.30 J</span>
