Answer and Explanation:
The basic unit which are that are important in chemistry are meter, kilogram ,mol,
Candela which is the unit of luminous of intensity is not so important in physics
(a) SI unit of length is meter (m)
(b) Si unit of volume is
(c) Si unit of mass is kilogram (kg)
(d) SI unit of time is second (s)
(e) SI unit of temperature is kelvin (K)
Answer:
Hiya! Your answer would be an Electromagnetic Wave.
Explanation:
Electromagnetic Wave is an electromagnetic wave that travels through space at the speed of light at about 300,000 kilometers per second. So when we talk about light traveling in waves, we can also talk about frequency, or the number of wavelengths that pass a certain point in a given length of time. We usually measure this as the number of wavelength cycles that pass per second. The units for this measurement are Hertz (hz).
So, if the wavelength of a light wave is shorter, that means that the frequency will be higher because one cycle can pass in a shorter amount of time. This means that more cycles can pass by the set point in 1 second. Likewise, a light wave that has a longer wavelength will have a lower frequency because each cycle takes a longer time to complete.
Hope I helped and I hope you get it right! :). Have a lovely day my friend!
~Bella
I would say B.
Explanation: Peer review improves the quality of research papers.
Answer:
So first thing to do in these types of problems is write out your chemical reaction and balance it:
Mg + O2 --> MgO
Then you need to start thinking about moles of Magnesium for moles of Magnesium Oxide. Based on the above equation 1 mole of Magnesium is needed to make one mole of Magnesium Oxide.
To get moles of magnesium you need to take the grams you started with (.418) and convert to moles by dividing by molecular weight of Mg (24.305), this gives you .0172 moles of Mg.
The theoretical yield would be the assumption that 100% of the magnesium will be converted into Magnesium Oxide, so you would get, based on the first equation, .0172 mol of MgO. Multiplying this by the molecular weight of MgO (24.305+16) gives us .693 g of MgO.
The percent yield is what you actually got in the experiment, and for this you subtract off the total mass from the crucible mass, or 27.374 - 26.687, which gives .66 g of MgO obtained.
Percent yield is acutal/theoretical, .66/.693, or 95.24%.
I'll let you do the same for the second trial, and average percent yield is just an average of the two trials percent yield.
Hope this helps.
