Answer:
1s² 2s²2p³
Explanation:
If the atom has seven electrons, it is Element 7 (nitrogen).
In the Periodic Table, you count the electrons in all the subshells up to
No. 7.
In the first Period, you have filled the 1s level (2 electrons).
In the second Period, you have filled the 2s subshell (2 electrons) and put three electrons in the 2p subshell.
Thus, the electron configuration is
1s² 2s²2p³
Note how the superscripts tell you the number of electrons in each subshell: <em>2 + 2 + 3 = 7</em>.
This is based on your personal opinion lol but ig you can say public speaking
<span>NH3 is the answer, if u look up its ph its a weak base</span>
Answer:
5.12x10¹¹ millimeters
Explanation:
Milli is a prefix used in science and engineering to decribe the number as the exponent x10⁻³. In the prefix kilo, the number is at the exponent x10³.
5.12x10⁵ kilometers are:
5.12x10⁵ kilometers * (1000m / 1km) = 5.12x10⁸ meters
5.12x10² meters * (1m / 1000millimeters) = 5.12x10¹¹ millimeters
Al
Explanation:
The limiting reactant will be Al:
4Al + 3O₂ → 2Al₂O₃
The limiting reactant is the reactant in short supply in a chemical reaction.
Given parameters:
Mass of Al = 30g Molar mass = 27g/mol
Number of moles =
= 
Number of moles of Al = 1.111 mole
Mass of O₂ = 30g, molar mass = 32g/mol
Number of moles =
= 0.94mol
In the reaction:
4 moles of Al reacted with 3 moles of O₂
1.11moles of Al will require
= 0.83mole to react
But we have been given 0.94mole of O₂. This is more than required.
Therefore O₂ is in excess and Al is the limiting reactant.
Learn more:
Limiting reagents brainly.com/question/6078553
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