Answer:
0.4444 g/cm³ ≅ 0.44 g/cm³ (2 significant figures).
Explanation:
<em>d = m/V,</em>
where, d is the density of the material (g/cm³).
m is the mass of the material (m = 28 g).
V is the volume of the material (V = 63.0 cm³).
<em>∴ d = m/V </em>= (28 g)/(63.0 cm³) = <em>0.4444 g/cm³ ≅ 0.44 g/cm³ (2 significant figures).</em>
Answer:
If I could have a super power it would be invisibility. Sometimes you wish you weren't there and if you were hiding from someone then they couldn't find you.
Answer:
![\% Cu=45.2\%\\\\\% Zn=53.6\%\\\\\% Pb=1.2\%](https://tex.z-dn.net/?f=%5C%25%20Cu%3D45.2%5C%25%5C%5C%5C%5C%5C%25%20Zn%3D53.6%5C%25%5C%5C%5C%5C%5C%25%20Pb%3D1.2%5C%25)
Explanation:
Hello!
In this case, given the masses of copper, zinc and lead, it is possible to compute the moles via their atomic masses first:
![n_{Cu}=\frac{91.0gCu}{63.55g/mol}=1.432mol\\\\ n_{Zn}=\frac{111gZn}{65.41g/mol}=1.697mol\\\\n_{Pb}=\frac{7.51gPb}{207.2g/mol}=0.0362mol\\](https://tex.z-dn.net/?f=n_%7BCu%7D%3D%5Cfrac%7B91.0gCu%7D%7B63.55g%2Fmol%7D%3D1.432mol%5C%5C%5C%5C%20n_%7BZn%7D%3D%5Cfrac%7B111gZn%7D%7B65.41g%2Fmol%7D%3D1.697mol%5C%5C%5C%5Cn_%7BPb%7D%3D%5Cfrac%7B7.51gPb%7D%7B207.2g%2Fmol%7D%3D0.0362mol%5C%5C)
Now, we compute the atomic percentages as shown below:
![\% Cu=\frac{1.432}{1.432+1.697+0.0362}*100\% =45.2\%\\\\\% Zn=\frac{1.697}{1.432+1.697+0.0362}*100\%=53.6\%\\\\\% Pb=\frac{0.0362}{1.432+1.697+0.0362}*100\%=1.2\%](https://tex.z-dn.net/?f=%5C%25%20Cu%3D%5Cfrac%7B1.432%7D%7B1.432%2B1.697%2B0.0362%7D%2A100%5C%25%20%3D45.2%5C%25%5C%5C%5C%5C%5C%25%20Zn%3D%5Cfrac%7B1.697%7D%7B1.432%2B1.697%2B0.0362%7D%2A100%5C%25%3D53.6%5C%25%5C%5C%5C%5C%5C%25%20Pb%3D%5Cfrac%7B0.0362%7D%7B1.432%2B1.697%2B0.0362%7D%2A100%5C%25%3D1.2%5C%25)
Best regards!
Answer:
The cycling of matter is important to many Earth processes and to the survival of organisms the existing matter must cycle continuously for this planet to support life Water, carbon, nitrogen, phosphorus, and even rocks move through cycles If these materials did not cycle, Earth could not support life.
Explanation:
Cold water<span> is </span>more dense<span> and will sink in room-temperature </span>water<span>. hope it helps :)</span>