Answer:
The concentration of the solution will be much lower than 6M
Explanation:
To prepare a solution of a solid, the appropriate mass is taken and accurately weighed in a weighing balance and then made up to mark with distilled water.
From
n= CV
n = number of moles m/M( m= mass of solid, M= molar mass of compound)
C= concentration of substance
V= volume of solution
m=120g
M= 40gmol-1
V=500ml
120/40= C×500/1000
C= 120/40× 1000/500
C=6M
This solution will not be exactly 6M if the student follows the procedure outlined in the question. The actual concentration will be much less than 6M.
This is because, solutions are prepared in a standard volumetric flask. Using a 1000ml beaker, the student must have added more water than the required 500ml thereby making the actual concentration of the solution less than the expected 6M.
a is the answer because all of the other answers are wrtong
Write an balance the equation
Na2O + H2O -> 2 NaOH
Calculate the molecular mass of Na2O and NaOH from the atomic mass from the periodic table.
Na = 23
O=16
H=1
Na2O = 23 * 2 + 16 = 62
NaOH = 23+16+1= 40
For the stoichiometry of the reaction one mole of Na2O = 62g produce two mol of NaOH = 2* 40= 80 g
120 g Na2O x 80g NaOH / 62g Na2O=
154.8 g NaOH
Reactants are the substance that undergo a change in a chemical reaction while products are what is produced after a reaction. don't have time to write a reaction.
Answer:
561 g P₂O₃
Explanation:
To find the mass of P₂O₃, you need to (1) convert moles H₃PO₃ to moles P₂O₃ (via mole-to-mole ratio from equation coefficients) and then (2) convert moles P₂O₃ to grams P₂O₃ (via molar mass). It is important to arrange the ratios/conversions in a way that allows for the cancellation of units. The final answer should have 3 sig figs to match the amount of sig figs in the given value.
Atomic Mass (P): 30.974 g/mol
Atomic Mass (O): 15.998 g/mol
Molar Mass (P₂O₃): 2(30.974 g/mol) + 3(15.998 g/mol)
Molar Mass (P₂O₃): 109.942 g/mol
1 P₂O₃ + 3 H₂O -----> 2 H₃PO₃
10.2 moles H₃PO₃ 1 mole P₂O₃ 109.942 g
---------------------------- x -------------------------- x ------------------- = 561 g P₂O₃
2 moles H₃PO₃ 1 mole