The charge of a proton is always +1
Answer:
B
Explanation:
First Law of thermodynamics says energy of the universe is constant and can only be changed in other forms of energy
Answer:
One of the bonds in nitrate is shorter than the other two.
Explanation:
We would firstly need to draw the Lewis structure for nitrate anion. To do this, let's follow the standard steps:
- calculate the total number of valence electrons: five from nitrogen, each oxygen contributes 6, so a total of 18 from oxygen atoms, as well as one from the negative charge, we have a total of 24 valence electrons;
- assign the central atom, usually this is the atom which is single; in this case, we have nitrogen as our central atom;
- assign single bonds to all the terminal atoms (oxygen atoms);
- assign octets to the terminal atoms and calculate the number of electrons assigned;
- the number of electrons assigned is 24, so no lone pairs are present on nitrogen;
- calculate the formal charges: each oxygen has a formal charge of -1 (formal charge is calculated subtracting the sum of lone pair electrons and bonds from the number of valence electrons of that atom); nitrogen has a formal charge of +2;
- nitrogen doesn't have an octet as well, so we'll both minimize its formal charge and make it obtain an octet if we make one double bond N=O.
Therefore, we may have 3 resonance structures, as this double bond might be formed with any of the 3 oxygen atoms.
By definition, double bonds are shorter than single ones, so one of the bonds is shorter than the other two.
Hey there!:
Molarity HCl = 3.5 M
Volume HCl = ?
Molarity NaOH = 2.0 M
Volume NaOH in liters = 50.0 mL / 1000 => 0.05 L
Number of moles NaOH:
n = M * V
n = 2.0 * 0.05
n = 0.1 moles of NaOH
Given the reaction:
HCl + NaOH = NaCl + H2O
1 mole HCl --------- 1 mole NaOH
1 mol HCl reacts with 1 mol NaOH , so moles NaOH = moles HCl
0.1 moles of NaOH = 0.1 moles of HCl
Therefore:
M( HCl ) = n / V
3.5 = 0.1 / V
V = 0.1 / 3.5
V = 0.029 L in mL : 0.029 * 1000 => 29.0 mL
hope that helps!
