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No expanded working has been attached for this question yet. The verified answer is Option C.

Examples of electromagnetic waves are radio waves, X-rays, gamma rays, light rays, etc

Let the count rate at zero time be N N \(\frac{3 min}{\to}\) \(\frac{N}{2}\) \(\frac{3 min}{\to}\) \(\frac{N}{4}\) \(\frac{N}{4}\) = 400 N = \(\frac{400}{N/4}\) x N = 1600

Let the count rate at zero time be N N \(\frac{3 min}{\to}\) \(\frac{N}{2}\) \(\frac{3 min}{\to}\) \(\frac{N}{4}\) \(\frac{N}{4}\) = 400 N = \(\frac{400}{N/4}\) x N = 1600

Once you figure out the electron configuration, you fill up the corresponding orbitals with electrons, any left with one is considered unpaired. Since 1s can only hold 2 electrons, and P has 15, that's obviously filled and has no unpaired electrons. The same is for 2s which holds 2, 2p which holds 6, 3s which holds 2. However 3p can hold 6 electrons and in order for that to be filled up you would need to have an element of 18 electrons. So you fill up as much as you can in 3p by first adding 1 electron to each energy level. 3p has 3 energy levels and there are only 3 electrons left to distribute, so each of those energy levels only gets 1, because you have to fill them all with one before you can start adding a second. So since you are only able to fill one electron in each of the three energy levels of the 3p orbital, that leaves the orbital open for 1 more electron in each of its energy levels. So there are 3 unpaired electrons in P.

Fractional distillation is used to separate mixtures into its component parts or fractions with the difference in boiling points between successive fractions must be more than 10^\circC. An example is the liquid nitrogen and oxygen are then separated by fractional distillation .

Using the combined gas law formula, In this problem, the oxygen is contained in a 2.76 L container at a temperature of 300 K. Since the gas remains in the same container and the temperature is not stated to change, both the volume( V) and the temperature (T) are constant. The Ideal Gas Law is defined as: PV = nRT Since the quantity of gas is reduced by one-half ( n\(_2\) = \(\frac{1}{2}\) n\(_1\)), the pressure must also be reduced by one-half. P\(_2\) = \(\frac{1}{2}\) P\(_1\) P\(_2\) = \(\frac{0.825}{2}\) = 0. 4125 atm Rounding to three decimal places (as provided in the options), the pressure is 0.413 atm.

They are the most stable due to having the maximum number of valence electrons their outer shell can hold. Therefore, they rarely react with other elements since they are already stable.

NH\(_4\)NO\(_3\) Ammonium Trioxonitrate(V) , unlike all other metallic trioxonitrates(v), decomposes on heating to give nitrogen(i)oxide N\(_2\)O and water.

The element is Phosphorus in group 5 with valencies of 3 and 5. The electronic configuration of phosphorus is 2,8,5. Hence it has two valencies of +5 and -3. Since we do not have 5 in the options provided, the valency is 3.

Duralumin is an alloy made up of 90% aluminum, 4% copper, 0.51% magnesium, and less than 1% manganese.

Polysaccharides are long chains of monosaccharides linked by glycosidic bonds. Three important polysaccharides, starch, glycogen, and cellulose, are composed of glucose.

Molar mass of methane = 16g/mol At S.T.P. its 8g occupies 11.2 so 16g occupies 22.4 dm\(^3\) Molar mass of propane = 44g/mol\(^-1\) occupies 22.4dm\(^3\) at S.T.P so 22g will occupy 11.2dm\(^3\)

Sulfuric acid is flushed with a mild, soapy solution if the burns are not severe. Sulfuric acid feels hot when water is added to the acid, but it is better to flush the area and not leave the acid on the skin. Don't try to neutralize the burn with acid or alkali. This could cause a chemical reaction that worsens the burn.

Charles' law describes the effect of temperature changes on the volume of a given mass of gas at a constant pressure.