<span>1.86 moles of hydrogen gas.
Since what the HCl is reacting with hasn't been mentioned, I'll assume zine. In that case, the balanced reaction is
Zn + 2HCl ==> ZnCl2 + H2
So for every 2 moles of HCl used, 1 mole of hydrogen gas will be generated. So let's figure out how many moles of HCl we have and then divide by 2.
Molarity is defined as moles/liter. So a 2.75 M HCl solution has 2.75 moles of HCl per liter. So the total number of moles we have is:
2.75 mole/L * 1.35 L = 3.7125 mol
And since we get 1 mole H2 per mole of HCl, we get:
3.7125 mol / 2 = 1.85625 mol
Rounding to 3 significant figures gives us 1.86 moles of hydrogen gas.</span>
It can be an element or a compound
While the material retains its chemical makeup, the physical property may be examined. The given statement is true.
The matter can undergo variations in physical or chemical properties. The physical changes of a matter occur when the matter undergoes changes in its physical properties like changes in the state of matter, weight, color, etc.
But the chemical composition of matter will remain constant if it undergoes a physical change. Whereas in chemical change, the matter undergoes a change in the composition of the substance but there will be no change in the physical properties.
Hence, The assertion is correct in that physical properties can be seen while the substance's chemical makeup stays constant.
To learn more about physical and chemical change, visit: brainly.com/question/21509240
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Explanation:
As a neutral lithium atom contains 3 protons and its elemental charge is given as
. Hence, we will calculate its number of moles as follows.
Moles = 
= 
= 100 mol
According to mole concept, there are
atoms present in 1 mole. So, in 100 mol we will calculate the number of atoms as follows.
No. of atoms = 
=
atoms
Since, it is given that charge on 1 atom is as follows.

= 
Therefore, charge present on
atoms will be calculated as follows.

Thus, we can conclude that a positive charge of
is in 0.7 kg of lithium.