Answer:
option A is the correct answer .
Explanation:
as density = mass per unit volume
density = 7.5/2.5 = 3 gm / cm³ ..is the answer ...
pls mark my answer as brainlist plzzzz and plz vote
Answer:Lithium
Explanation:Lithium has 3 protons, and 4 neutrons making it the lightest element that isn't a gas.
How many grams of Cu would be needed to react with 2.0 mol HNO3?
<span>by the equation </span>
<span>3Cu + 8HNO3 --> 3Cu(NO3)2 + 2NO + 4H2O </span>
<span>2.0 mol HNO3 reacts with 3/8 ths as many moles of Cu = 0.75 moles of Cu </span>
Hello.
This experiment proved that atoms are not massive, they have large blanks inside the structure. Therefore, models like Thomsom's and Dalton's weren't good enough to describe the comportment of these units. A model of an atom like a <em>planetary system</em> was elaborated after this.
