First find the moles
moles of the calcium= 72.8 / 40
moles of calcium in 72.8g = 1.82mol
number of atoms= moles x Avogadro constant
atoms = 1.82 x 6.02x10+23
so the number of atoms is 1.096x10+24
Answer:
Visible light contains all the colors from violet to red. An object gets its color when electrons absorb energy from the light and become “excited” (raised to a state of increased energy). The excited electrons absorb certain wavelengths of light.
The Sun emits light of every possible frequency at once, including at frequencies too high or too low for us to see. But the Sun's highest intensity radiation aligns approximately with our visible range – red through blue. That's no coincidence – like all animals on Earth, we have evolved to make best use of the light available.
Explanation:
Answer:
False
Explanation:
Changing the coefficients is one of the steps of balancing a chemical equation. Changing the subscript changes the compounds being used, while changing the coefficient changes the amount of each compound being used.
Answer: Because water has a high specific heat capacity due to the hydrogen bonding within the H₂O molecules ; so it takes a great deal of energy, or heat, to break these bonds— or to form them.
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