Answer:
Q.89
Alkane - CnH(2n+2)
given that 8 H = > 8= 2n+2
therefore n= 3
C3H8 = 12×3 + 8×1= 36 +8 = 44
Answer:
Density of concentrated H2SO4 = 1.99g/cm^3 = 1991.79Kg/m^3
Explanation:
mass of empty flask = 78.23g mass of flask filled when with water = 593.63g.
mass of flask filled when with concentrateds sulfuric acid, H2SO4 = 1026.57g
Mass of water = (mass of flask filled when with water) -
(mass of empty flask) = 593.63g - 78.23g = 515.4g
Volume of flask = volume of water = volume of concentrateds sulfuric acid, H2SO4 =
(mass of water)/ density of water) = 515.4g/1.00g/cm^3 = 515.4cm^3
The density of concentrated sulfuric acid is given by
Density of concentrated H2SO4 = (mass of H2SO4) ÷ (volume of H2SO4) = 1026.57g/515.4cm^3 = 1.99g/cm^3 = 1991.79Kg/m^3
Answer:
2Ag (s) + 2HNO3 (aq) → 2AgNO3 (aq) + H2(g)
Explanation:
Usually, metals displace hydrogen from dilute acids to form the corresponding salt of the metal and hydrogen. This in turn depends on the position of the metal in the electrochemical series. Metals below hydrogen in the electrochemical series cannot spontaneously displace it from dilute acids. Silver is below hydrogen in the electrochemical series, hence it cannot spontaneously displace hydrogen from dilute nitric acid as shown in the answer.
Answer:
Astatine is a halogen with several isotopes that all have short half-lives.
Which of the following combinations of mass number and neutrons are possible as isotopes of astatine? Choose one or more:
i) A = 211, n = 127
ii) A = 210, n = 125
iii) A = 220, n = 134
iv) A = 207, n = 122
v) A = 209, n = 124
Explanation:
The mass number is the sum of the number of protons and the number of neutrons in an atom.![A=no.of protons+no.of neutrons\\=>no.of neutrons=A-no.of protons\\](https://tex.z-dn.net/?f=A%3Dno.of%20protons%2Bno.of%20neutrons%5C%5C%3D%3Eno.of%20neutrons%3DA-no.of%20protons%5C%5C)
Atomic number of At(astatine ) =85
That means it has --- 85protons.
Its mass number A=210
Hence, the number of neutrons in At are:
![n=A-Z\\=>n=210-85\\=>n=125](https://tex.z-dn.net/?f=n%3DA-Z%5C%5C%3D%3En%3D210-85%5C%5C%3D%3En%3D125)
Second option:
ii) A=210 , n=125 is the answer.
Answer:
They are all organic compounds
Explanation:
Methanol, ethanoic acid and glucose are all organic compound that can be found in living organisms.
Glucose is a product of photosynthesis in plants. It is also produced from digestion of food in animals.
Ethanoic acid is a product of cellular respiration that occurs where there is insufficient oxygen.
Methanol is a waste often found in urine.
These compounds can all be traced to living sources. They are called organic compounds.