Answer:
A) False
B) True
C) True
D) True
Explanation:
A) False. If the charge of the atom is +2 means that you have two protons more than number of electrons. If you have 36 electrons you must have <em>38 protons.</em> Also, the electrons are not in the nucleus.
B) True. The isotope of X contains 38 protons, two more than the electron number.
C) True. The mass number is the number of protons + number of neutrons.
If the mass number is 79 and there are 38 protons you must have 41 neutrons.
D) True. You can now the identity of the atom with the number of protons that is the same than atomic number. The strontium, Sr, is the atom with 38 as atomic number.
I hope it helps!
Commercialism is when one benefits while the other gets no harm nor benefit.
Example: the Remora rides attached to bigger types of fish or shark and eat the remains of meals left behind from the organism they are attached to.
Parasitism is when benefits and the other is harmed.
Example: A tape worm feeds off the intestines and eat what the host eats, killing the host because they are deprived of nutrients.
Mutualism is when both benefit.
Example: when a bird is allowed to peck the food from a rhinos mouth to help the rhinos teeth and allows the birth food.
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>
<span>explain why the dissolved component does not settle out of a solution -
</span><span>Before saturation, there are attractive forces between solute and solvent. after saturation, the capacity for the attractive forces is reached and no more solute can be dissolved</span>
