Percent by mass of platinum in white gold = 100% - 45% = 55%
We let x be the mass of the white which is 45% gold and 55% platinum.
Mass of gold in white gold = m x 0.45
where m is the total mass.
From the given above, we formulate the equation that would allow us to determine the mass of white gold.
154 = x (0.45)
x = 342.22 g
Then, we determine the amount of platinum.
mass of platinum = (342.22 g)(0.55)
mass of platinum = 188.22 grams
Thus, 188.22 grams of platinum is needed.
Answer:
Explanation:
Area of a circular hubcap is 615 square inches
Area of a circular shaped object is given by :

r is radius of hubcap.
If the radius of the hubcap were quadrupled, it means r' = 4r. New area will become:

A' is new area

New area of the hubcap is 9840 square inches.
moles NaOH = 5.20 g * 1 mol / 40.00 g = 0.13 mol
[NaOH] = n/V = 0.13 mol / 0.500L
= 0.26 M
The answer to this question is 0.26 M
The awnser is C on edge 2020
D)plastic copper
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