Answer is: c. It is incorrect because sodium phosphate is a compound that has a single composition.
Sodium phosphate is chemical compound composed of atoms connected with chemical bonds.
Pure substance is made of only one type of atom (element) or only one type of molecule (compound), it has definite and constant composition with distinct chemical properties.
Pure substances can be separated chemically, not physically, that is difference between pure substances and mixtures.
Answer:
i think that the answer is solid liquid and gas.
Explanation:
X ml - <span>25% alcohol mixture
y ml - </span><span>90% alcohol mixture
x+y = 455
0.25x ml alcohol in </span>x ml of 25% alcohol mixture
0.9y ml alcohol in y ml of 90% alcohol mixture
0.75*455= 341.25 ml alcohol in 455 ml of 75% alcohol mixture
0.25x+0.9y=341.25
System of equations:
x+y = 455 /*(-0.25) ------> -0.25x-0.25y = -0.25*455
0.25x+0.9y=341.25
-0.25x-0.25y=-113.75
0.25x+0.9y=341.25 Add both equations
0.25x+0.9y-0.25x-0.25y=341.25-113.75
0.65y =227.5
y=227.5/0.65 = 350 ml of 90% alcohol mixture
x+y=455
x+355=455
x=100 ml of 25% alcohol mixture
Answer:
429.4 kJ are absorbed in the endothermic reaction.
Explanation:
The balanced chemical equation tells us that 1168 kJ of heat are absorbed in the reaction when 4 mol of NH₃ (g) react with 5 mol O₂ (g).
So what we need is to calculates how many moles represent 25 g NH₃(g) and calculate the heat absorbed. (NH₃ is the limiting reagent)
Molar Mass NH₃ = 17.03 g/mol
mol NH₃ = 25.00 g/ 17.03 g/mol = 1.47 mol
1168 kJ /4 mol NH₃ x 1.47 mol NH₃ = 429.4 kJ
