Answer is (4).<span>
<em>
</em></span>
<span><em>Explanation:</em>
</span><span>
<span>The given mixture contains an </span>insoluble solid<span> <span>and an </span></span>aqueous solution of salt. <span>The insoluble solid is </span>sand. <span>
First </span><span>we have to separate </span>insoluble solid. <span>Sand can be separated by doing </span>filtration. When we filter the mixture sand can be seen as the residue on the filter paper.
<span>After filtering the mixture, we should collect the </span>filtrate. <span>Filtrate is the </span>salt solution. <span>By doing </span>evaporation <span>we can get the </span>solid salt. <span>
First </span>and second choices are wrong <span>because </span>after evaporating water filtration
cannot be done and salt and sand will be mixed together.<span>
Salt cannot be
filtered out because the salt is soluble and it is <span>in
aqueous medium. Hence, third choice is wrong</span></span></span>
Answer:
2 Hertz
Explanation:
<em>The frequency would be 2 Hertz.</em>
<u>The frequency of a wave is defined as the rate at which the particles of a medium vibrates when the wave is passed through it while the period of a wave is the time it takes the particles to make a complete cycle of vibration.</u>
The frequency of a wave is inversely related to its period and is defined by the following equation:
f = 1/t, where f is the frequency (in hertz) and t is the period (in seconds).
Hence, if the period of a ripple is 1/2 or 0.5 seconds, the frequency becomes;
f = 1/0.5 = 2 Hertz
<span>Lithium has a property
of high reactivity and to obtain lithium is through electrolysis of its fused
salts. Because lithium is very reactive, it is not found free so electrolysis
is use to split it apart to get it. Moreover,
Lithium is an alkali metal with single valence electron that is easily given up
to form cation, which make it a good conductor of heat and electricity.</span>
<span> </span>
yeag
Explanation:
2SrO + 4NO2 + O. The thermal decomposition of strontium nitrate to produce strontium oxide, nitrogen dioxide and oxygen. This reaction takes place at a temperature of over 570°C