For the whole set of problems, always remember the Avogadro’s number is 6.023*10^23 units per mole of a substance. Units could be atoms, molecules or formula units.
The first question asks for the number of molecules of NaNO3. The molar mass of NaNO3 is 85 grams per mole. So,
150g NaNO3(1mole NaNO3/85 grams NaNO3)(6.023*10^23 molecules/1mole NaNO3)=1.063*10^24 molecules of NaNO3
5.7*10^46 molecules of NaNO3(1mole NaNO3/6.023*10^23 molecules)(85 grams NaNO3/1mole NaNO3) = 8.044*10^24 grams NaNO3
For the molar mass of water, we have 18.02grams per mole.
301 moles H2O(18.02 grams H2O/1 mole H2O) = 5424.02 grams H2O
For the molar mass of sulfuric acid, we have 98.08 grams per mole.
25g H2SO4(I mole H2SO4/98.08g H2SO4) = 0.2549 mole H2SO4
For the molar mass of Ca(OH)2, we have 74.1 grams per mole.
252gCa(OH)2(1mol/74.1g)(6.023*10^23/1mol) = 2.048*10^24 molecules of Ca(OH)2
For the molar mass of calcium, we have 40 grams of Ca per mole.
6.7*10^35 atoms Ca(1 mole Ca/6.023*10^23 atoms)(40g Ca/1mol Ca) = 4.45*10^13 grams Ca
The typical measure for the distance between stars is the light-year. Light-year and parsec are units used to quantify the enormous distances in the universe.
The distance between stars is typically measured in light-years. This term, 'light-year', refers to the distance that light can travel in one year, which is approximately 9.461 trillion kilometers or 5.879 trillion miles. Another less commonly used unit is the parsec, which is equivalent to about 3.26 light years. Such large units are necessary due to the vast distances between stars in the universe.
So, The distance between stars is typically measured in light-years.
#SPJ6
Carbon disulfide is formed by a direct reaction of carbon and sulfur. At room temperature, CS2 is a colorless liquid with an offensive odor. Carbon disulfide vapors are flammable.
59 Identify one physical property and one chemical property of CS2. [1]
Answer: Physical property of is state of matter (liquid) and it is a chemical compound.
Explanation:
Chemical property is defined as the property of a substance which is observed during a reaction where the chemical composition identity of the substance gets changed.
Physical property is defined as the property which can be measured and whose value describes the state of physical system. For Example: State, density etc.
Carbon disulfide is the compound which is formed by the chemical combination of carbon and sulfur atoms. The equation for this follows:
The chemical property of carbon disulfide is different from that of carbon and sulfur. Thus, this is a chemical compound.
It is given, that this compound is a colorless liquid, which means that the state of this compound is liquid state.
Hence, physical property of is state of matter (liquid) and it is a chemical compound.
The physical property of carbon disulfide is that at room temperature, CS2 is a colorless liquid with an offensive odor. The chemical property of carbon disulfide is that it is formed by a direct reaction of carbon and sulfur.
Answer:
X=600 degrees celsius
Explanation:
We can evaluate by using the equation ==> Q=m(c)(delta T)
-We know the mass is 0.3 g
-Q= 66,300 J
-C= 390 j/g 0C
-Therefore, we need to solve for delta T (which will be represented by x)
Q= mct
66,300 J= 0.3 g (390 J/g 0C) (t)
The unit of measurement (g-grams) can be crossed out on the left side of our expression.
66,300 J=0.3(390 J 0C) (t)
-If we convert into a proportional relationship:
66,300 J 117 J/0C x
------------ = -----------
117 J/0C 117 J/0C
-Joules on both sides can be crossed off
*117 J/0C came from the product in terms of 0.3(390 J 0C)
*If we find the quotient of 66,300 J and 117 J/0C, we get 566.6 repeating
-You may keep the answer as it is, although for simplicity reasons, we can round to the nearest hundred.
-Therefore, x=600.
-----Remember, x represented the delta t in our equation. (I made notice of that when evaluating).
Hope this helps! :)
Answer:
4.907 × 10^-19 J
Explanation:
The energy of the lasers in a Blu-ray player can be calculated by using;
E = hf
Where;
E = Energy of laser (J)
h = Planck's constant (6.626 × 10^-34 J/s)
f = frequency (Hz)
However, the frequency must be known first in order to calculate the energy. The frequency can be calculated using the formula:
f = v/λ
Where:
λ = wavelength (4.05x10−7 m.)
v = speed of light (3 × 10^8m/s)
f = frequency (Hz)
f = 3 × 10^8 ÷ 4.05 x 10^−7
f = 0.7407 × 10^(8 + 7)
f = 0.7407 × 10^15
f = 7.407 × 10^14 Hz
Using E = hf
E = 6.626 × 10^-34 × 7.407 × 10^14
E = 49.07 × 10^(-34 + 14)
E = 49.07 × 10^-20
E = 4.907 × 10^-19 J