All forces of energy are useful at home, like friction, friction can let us grip to the ground, or mechanical energy, used in cars because cars move, and computers same thing you move the mouse, type and do way more. Energy is always around us.
Is that all? That doesn’t help us give the answers
All the electrons orbit the nucleus in specific orbitals
Find molar mass of MgCl2 so M=<span>95.211 g/mol
N=m/M
N=332/95.2
N=3.487
dont forget to round your sig figs </span>
D, 2Cu + O2 → 2CuO. A is wrong because oxygen is a diatomic element, meaning it always has to come in the form of O2 in the case of gas. B is wrong because the equation isn't balanced correctly; there's two oxygens on the reactants side, while only one oxygen on the products side. C is wrong because it's saying you're STARTING OUT with CuO already: that doesn't correspond with the word problem. Thus leaves D, where the equation is balanced correctly, has the diatomic oxygen, and ends with CuO.
