Given the wavelength of the yellow light (700 nm. in this case) we can find the frequency
<span>by dividing the speed of light c by the wavelength w, that is: f = c/w and we know that </span>
<span>c is equal to 2.998 * 10**8 meters per second. </span>
<span>So the frequency f = (2.998 * 10**8) / (7.0 * 10**-7) = 4.283 * 10**14 cycles per sec. </span>
<span>(or Hz.) Since the threshold frequency of Cs is 9.39 * 10**14 Hz, the red light doesn't </span>
<span>have a high enough frequency (or energy) to cause electron emission. </span>
<span>Hope this answers your question.</span>
Answer:
The correct answer would be - observing with the help of five senses.
Explanation:
To find and describe the physical properties of the given substance or the solution or liquid students can observe using their five senses. By looking at the liquid one can find its state and color, by smelling students can find the odor of the sample, by touching it one can observe and describe the texture.
Fluidity can also be measure by the touch if the solution is viscous or free-floating. By using a thermometer and using a graduated cylinder one can find the temperature at room temperature and the weight of substance respectively.
In chemistry, a synthetic element is a chemical element that does not occur naturally on Earth, and can only be created artificially. So far, 24 synthetic elements have been created (those with atomic numbers 95–118). All are unstable, decaying with half-lives ranging from 15.6 million years to a few hundred microseconds.
Here is a picture am if It doesn't show up, I am sorry
Test tube of ammonium chloride (NH4Cl) being heated over a bunsen burner flame. Ammonium chloride decomposes readily when heated, but condenses in the cooler area at the top of the test tube. This is a reversible reaction, where the ammonium chloride decomposes into the gases ammonia (NH3) and hydrogen chloride (HCl).
Answer: D, splitting water into hydrogen and oxygen is a chemical change.