Answer:
The correct option is;
D. All the elements in families 1 and 2 can place all their shell electrons in the s sub-level
Explanation:
The elements in families 1 and 2 also called the group 1A and group 2A elements are known as the alkali and alkaline earth metals. The elements in the families 1 and 2 are also referred to as the s-block elements as they have their valence electrons which are 1 and 2 respectively, in the s-orbital or s sub-level
Due to their low ionization energy, and the ease with which they donate their valence electrons, elements of the families 1 and 2 are known to be very reactive, and are found in a combined state in nature.
Thermal expansion<span> is the tendency of matter to change in shape, area, and volume in response to a change in temperature, through heat transfer. Temperature is a monotonic function of the average molecular kinetic energy of a substance. When a substance is heated, the kinetic energy of its molecules increases.</span>
90 grams due to laws of conservation of mass. Output mass = input mass. Mass can never be created or destroyed.
The answer:
all that we search for is the number of mole of HCl and the number of mole of C2H6O
M(HCl) = 5.5g/ mole of HCl , so mole of HCl = 5.5/M(HCl), where M(HCl) is the molar mass.
M(HCl) = 1+ 36.5= 37.5
moles of HCl = 5.5/37.5=0.14
M(C2H6O) = 200g / moles of C2H6O, so moles of C2H6O=200g / M(C2H6O)
M(C2H6O)= 2x12+ 6 + 16=46,
moles of C2H6O=200g / 46 =<span>4.35 </span><span> moles
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the sum of the moles is 0.14 + <span>4.35 </span> = 4.501 moles
finally, <span>The mole fraction of hcl in a solution prepared by dissolving 5.5 g of hcl in 200 g of c2h6o is 0.031
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because it can be found by 0.14 / 4.501= 0.031
<span>You need to consider the valences of the two elements. Potassium is +1; nitrogen is -3. To balance the molecule, you need 3 potassium to one nitrogen, or K3N</span>
