Answer: -
6
Explanation: -
The given unbalanced chemical equation is As + NaOH -- > Na3AsO3 + H2
We see there 3 sodium on the right side from Na3AsO3.
But there are only 1 sodium on the left from NaOH.
So we multiply NaOH by 3.
As + 3 NaOH -- > Na3AsO3 + H2
Now we see the number of Hydrogen on the left is 3.
But the number of hydrogens is 2 on the left.
So, we multiply to get both sides 6 hydrogen.
As + 6NaOH -- > Na3AsO3 + 3 H2
Rebalancing for Na,
As + 6NaOH -- > 2Na3AsO3 + 3 H2.
Finally balancing As,
2 As + 6 NaOH -- > 2Na3AsO3 + 3H2
The coefficient of the NaOH molecule in the balanced reaction is thus 6
Answer : The wavelength is 
Solution : Given,
frequency = 29.2 Hz
Formula used :
where,
= frequency
= wavelength
c = speed of light = 
Now put all the given values in this formula, we get the wavelength.
Therefore, the wavelength is
Answer:
Mg(NO4)2 is 180.3 g/mol
Explanation:
First find the substance formula.
Magnesium Nitrate.
Magnesium is a +2 charge.
Nitrate is a -1 charge.
So to balance the chemical formula,
We need 1 magnesium atom for every nitrate atom.
2(1) + 1(-2) = 0
So the substance formula is Mg(NO4)2.
Now find the molar mass of Mg(NO4)2.
Mg = 24.3 amu
N = 14.0 amu
O = 16.0 amu
They are three nitrogen and twelve oxygen atoms.
So you do this: 24.3 + 14.0(2) + 16.0(8) = 180.3 g/mol
So the molar is mass is 180.3 g/mol.
The final answer is Mg(NO4)2 is 180.3 g/mol
Hope it helped!
