Answer is (4).<span>
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<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>
The correct answer is a descriptive investigation.
An investigation which does not involve hypotheses called descriptive investigation.
Hypotheses are termed as scientific hypotheses and require that one can test it. In hypothesis, previous observation can not satisfactorily be explained with an available scientific theory.
Working hypotheses are being proposed for further research.
The answer is C. because the dwarf planet's orbit lies between mars and Jupiter but it orbits the sun. Hope it helped!
She will most likely observe that the temperature
does not change during melting because the heat absorbed is used to overcome
intermolecular forces rather than to increase the kinetic energy of the
particles if she measures the temperature of the water in the beaker.
Answer:
Heat flows from the block at high temperature to the one with lower temperature
Explanation:
The direction of heat flow is from a body at higher temperature to one with a lower temperature.
- Temperature gradient determines the way and manner in which heat is dissipated.
- As a system tend to increase entropy, it ensures that heat moves from hotter body to a colder body.
- Heat movement here is by conduction as the body touches.
- When both bodies reaches the same temperature, thermal equilibrium is established.
