Answer:
Cookies definitely obeys the law of conservation.`
Explanation:
As, When Maria mixes up the ingredients, Water was also one among them
And, Initially When she was measuring the weight of Ingredients, Weight of Water was coming,
But,
When She baked the cookies , water from the cookies got evaporated , and thus weight coming was decreased finally.
Considering Cookies and Environment Whole as a system You can clearly say that they obeys Law of conservation of mass , As Water is present in Environment for now.
Answer:
The answer to your question is letter B.
Explanation:
Process
1.- Calculate the molecular mass of Ferric oxide
Fe = 56g x 2 = 112 g
O = 16 x 3 = 48 g
Mass = 112 + 48 = 160 g
2.- Calculate the mass of 0.7891 moles of Ferric oxide
160 g of Fe₂O₃ ------------- 1 mol
x ------------- 0.7891 mol
x = (160 x 0.7891) / 1
x = 126.2 g
Answer:
44.63g
Explanation:
First, let us calculate the number of mole of KBr in 1.50M KBr solution.
This is illustrated below:
Data obtained from the question include:
Volume of solution = 250mL = 250/1000 = 0.25L
Molarity of solution = 1.50M
Mole of solute (KBr) =.?
Molarity is simply mole of solute per unit litre of solution
Molarity = mole /Volume
Mole = Molarity x Volume
Mole of solute (KBr) = 1.50 x 0.25
Mole of solute (KBr) = 0.375 mole
Now, we calculate the mass of KBr needed to make the solution as follow:
Molar Mass of KBr = 39 + 80 = 119g/mol
Mole of KBr = 0.375 mole
Mass of KBr =?
Mass = number of mole x molar Mass
Mass of KBr = 0.375 x 119
Mass of KBr = 44.63g
Therefore, 44.63g of KBr is needed to make 250.0mL of 1.50 M potassium bromide (KBr) solution
Answer:
At
Explanation:
atomic mass increases as you go down a group
Answer:
0.088mole
Explanation:
Given parameters:
Mass of the compound = 5.125g
Unknown:
Number of moles = ?
Solution:
To solve this problem, we need first find the molar mass of the given compound.
Molar mass of NaCl = 23 + 35.5 = 58.5g/mol
So;
Number of moles = 
= 
= 0.088mole
