Answer:
History of composition
Years Material Weight (grains)
1944–1946 gilding metal (95% copper, 5% zinc) 48 grains
1947–1962 bronze (95% copper, 5% tin and zinc) 48 grains
1962 – September 1982 gilding metal (95% copper, 5% zinc) 48 grains
October 1982 – present copper-plated zinc (97.5% zinc, 2.5% copper) 38.6 grains
The mass of Ba(IO3)2 that can be dissolved in 500 ml of water at 25 degrees celcius is 2.82 g
<h3>What mass of Ba(IO3)2 can be dissolved in 500 ml of water at 25 degrees celcius?</h3>
The Ksp of Ba(IO3)2 = 1.57 × 10^-9
Molar mass of Ba(IO3)2 = 487 g/mol?
Dissociation of Ba(IO3)2 produces 3 moles of ions as follows:

![Ksp = [Ba^{2+}]*[IO_{3}^{-}]^{2}](https://tex.z-dn.net/?f=Ksp%20%3D%20%5BBa%5E%7B2%2B%7D%5D%2A%5BIO_%7B3%7D%5E%7B-%7D%5D%5E%7B2%7D)
![[Ba(IO_{3})_{2}] = \sqrt[3]{ksp} =\sqrt[3]{1.57 \times {10}^{ - 9} } \\ [Ba(IO_{3})_{2}] = 1.16 \times {10}^{-3} moldm^{-3}](https://tex.z-dn.net/?f=%5BBa%28IO_%7B3%7D%29_%7B2%7D%5D%20%3D%20%20%5Csqrt%5B3%5D%7Bksp%7D%20%3D%3C%2Fp%3E%3Cp%3E%5Csqrt%5B3%5D%7B1.57%20%5Ctimes%20%20%7B10%7D%5E%7B%20-%209%7D%20%7D%20%5C%5C%20%20%5BBa%28IO_%7B3%7D%29_%7B2%7D%5D%20%3D%201.16%20%5Ctimes%20%20%7B10%7D%5E%7B-3%7D%20moldm%5E%7B-3%7D)
moles of Ba(IO3)2 = 1.16 × 10^-3 × 0.5 = 0.58 × 10^-3 moles
mass of Ba(IO3)2 = 0.58 × 10^-3 moles × 487 = 2.82 g
Therefore, mass Ba(IO3)2 that can be dissolved in 500 ml of water at 25 degrees celcius is 2.82 g.
Learn more about mass and moles at: brainly.com/question/15374113
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Answer:
A the uneven heating of earths surface
Explanation:
Because earths rotates on its axis, circulating air is deflected torward the right in the northern hemisphere and toward the left Southern Hemisphere. This is called the coriolis effect
Oxygen is something that activated Cellar Reapiration that convets nutrients into energy (ATP).