Answer:
The mass percentage of the solution is 10.46%.
The molality of the solution is 2.5403 mol/kg.
Explanation:
A bottle of wine contains 12.9% ethanol by volume.
This means that in 100 mL of solution 12.9 L of alcohol is present.
Volume of alcohol = v = 12.9 L
Mass of the ethanol = m
Density of the ethanol ,d= ![0.789 g/cm^3=0.789 g/mL](https://tex.z-dn.net/?f=0.789%20g%2Fcm%5E3%3D0.789%20g%2FmL)
![1 cm^3=1 mL](https://tex.z-dn.net/?f=1%20cm%5E3%3D1%20mL)
![m=d\times v=0.798 g/ml\times 12.9 mL = 10.1781 g](https://tex.z-dn.net/?f=m%3Dd%5Ctimes%20v%3D0.798%20g%2Fml%5Ctimes%2012.9%20mL%20%3D%2010.1781%20g)
Mass of water = M
Volume of water ,V= 100 mL - 12.9 mL = 87.1 mL
Density of water = D=1.00 g/mL
![M=D\times V=1.00 g/ml\times 87.1 mL =87.1 g](https://tex.z-dn.net/?f=M%3DD%5Ctimes%20V%3D1.00%20g%2Fml%5Ctimes%2087.1%20mL%20%3D87.1%20g)
Mass percent
![(w/w)\%=\frac{m}{m+M}\times 100](https://tex.z-dn.net/?f=%28w%2Fw%29%5C%25%3D%5Cfrac%7Bm%7D%7Bm%2BM%7D%5Ctimes%20100)
![\frac{10.1781 g}{10.1781 g+87.1 g}\times 100=10.46\%](https://tex.z-dn.net/?f=%5Cfrac%7B10.1781%20g%7D%7B10.1781%20g%2B87.1%20g%7D%5Ctimes%20100%3D10.46%5C%25)
Molality :
![m=\frac{m}{\text{molar mass of ethanol}\times M(kg)}](https://tex.z-dn.net/?f=m%3D%5Cfrac%7Bm%7D%7B%5Ctext%7Bmolar%20mass%20of%20ethanol%7D%5Ctimes%20M%28kg%29%7D)
M = 87.1 g = 0.0871 kg (1 kg =1000 g)
![=\frac{10.1781 g}{46 g/mol\times 0.0871 kg}](https://tex.z-dn.net/?f=%3D%5Cfrac%7B10.1781%20g%7D%7B46%20g%2Fmol%5Ctimes%200.0871%20kg%7D)
![m=2.5403 mol/kg](https://tex.z-dn.net/?f=m%3D2.5403%20mol%2Fkg)
Answer:- d. London dispersion
Explanations:- Carbon dioxide structure is given below:
O=C=O
It has two polar C=O bonds but even then it is non polar molecule as it's linear and the dipole moment of one C=O bond is canceled by it's opposite C=O bond.
being non polar, the only attraction forces present in it are London dispersion forces.
Maybe 4mL cause it sounds like a math problem so that should be it
Explanation:
Metals tend to have 1-3 valence electrons in their outer shell, while non metals have 4-8 electrons in their outer shell. Metals are natural elements that are hard, opaque, shiny and dense. While non metals are chemical substances that are soft, transparent, non-shiny and brittle. You can also distinguish a metal from a non-metal based on its appearance: metals are Lustrous while non metals are Non-lustrous. In other words metals are shiny while non metals are usually dull or simply "not shiny". Melting and Boiling point can also help distinguish between metals and non metals: metals tend to have : very high melting and boiling point. Nonmetals have Low melting and boiling point. Metals are also good conductors of heat and electricity, while nonmetals are poor conductor of heat and electricity. And lastly, metals are malleable and are always hard except for sodium, and nonmetals are non-malleable and are soft except for diamonds.
Answer:
9,480 mg
Explanation:
he average caffeine content of an 8-oz, brewed cup of coffee is 95 mg. A single espresso or espresso-based drink contains 63 mg, and decaf coffee contains about 3 mg of caffeine (on average).