Answer:
454.3 g.
Explanation:
1.0 mol of CaO liberates → – 64.8 kJ.
??? mol of CaO liberates → - 525 kJ.
∴ The no. of moles needed = (1.0 mol)(- 525 kJ)/(- 64.8 kJ) = 8.1 mol.
<em>∴ The no. of grams of CaO needed = no. of moles x molar mass</em> = (8.1 mol)(56.077 g/mol) = <em>454.3 g.</em>
<span>The mass of an object is measured in either grams or kilograms. Mass is best described as the amount of matter, or "stuff," in a solid, and is different from weight (which is the force of gravity on an object). Since mass is used with solids, it will be measured in grams or kilograms (rather than in something like liters, which would be used with the volume of a liquid). To measure mass, you can use a balance, for example a triple balance beam.</span>
Answer:
Energy in the campfire originates from the potential chemical energy of the wood, before it is burnt to warm and give light around the campfire.
Explanation:
For a camp fire, the energy input is in the form of the potential chemical energy, stored up in the firewood used to fuel the flame.
The energy output is in the form of heat energy that the campfire radiates all around, light energy given off from the flame, and a little bit of sound energy, heard in the cracking of the firewood as they burn in the flame.
chemical energy ⇒ heat energy + light energy + sound energy
Answer:
H. 2 blue, 3 yellow, and 12 green
Explanation:
Aluminium atoms (Al) = Blue Beads
Oxygen Atoms (O) = Green Beads
Sulfur (S) = Yellow beads
From the compound Al2(SO4)3, the number of atoms present are;
Al = 2
S = 3
O = 12
This means the model would contain;
2 Blue beads
12 Green beads
3 Yellow beads
The correct option is; H. 2 blue, 3 yellow, and 12 green