Intensity has no affect on whether or not the photoelectric effect occurs. The determining property is frequency and since frequency and wavelength are inversely proportional, wavelength matters as well. If a frequency of light can't cause the photoelectric effect to happen, no matter what the intensity is, the light can't make it happen.
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The molarity of a solution is a type of expression of concentration equal to the number of moles solute per liter solution. In this problem, we are given the molarity equal to 0.75 M and a volume equal to 500 milliliters. <span>500 milliliters is equal to 0.5 liters. we multiply M and L to get the number of moles then multiply by the molar mass of NaCl. The answer is 21.92 grams.</span>
Compressions are regions of high pressure due to particles being close together
rarefactions are regions of low pressure due to particles being spread further apart
Longitudinal waves are often demonstrated by pushing and pulling a stretched slinky spring