Answer:
Explanation:
An element whose atomic number is 68 (number Z), has 68 electrons and 68 protons. According to the periodic table it corresponds to the element Erbium (Er), whose mass number (A) is 167. The number of neutrons is 167-68 = 99.
I’m guessing you mean moles. So the big M stands for mol/L. That means first you’d want to convert your mL to L. To do this write your 250mL then make parenthesis for the conversion. 1L=1000mL
250mL(1L/1000mL). Since the mL is on the bottom in the parenthesis we can cancel them out. Now all we do is divide and keep the L.
.250L is what you get. Now we need to figure out how to cancel the L with what we have left. We know M stands for Moles/L so this means in order to get ride of L we need to multiply our new number times the 1.5
.250L X 1.5 moles
_______
1L
This gives us 0.375 moles NH4SO4
They found that difference occurs in the speed of both sound and charges occur due to the difference in the type of medium.
Sound and charges needs specific medium for faster movement i.e. sound moves faster in solid as compared to liquid and gas whereas charges moves faster and easily in gold due to lower resistance which is followed by copper. Sound can move from solid, liquid and gases whereas charges move only in solid metal in which free electrons are present. The speed of sound and flow of current are affected due to difference in the arrangement of atoms in solid, liquid and gas.
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