To determine the mass of the hydrogen gas that was collected, we calculate for the moles of hydrogen gas from the conditions given. In order to do this, we need an equation which would relate pressure, volume and temperature. For simplicity, we assume the gas is an ideal gas so we use the equation PV = nRT where P is the pressure, V is the volume, n is the number of moles of the gas, T is the temperature and R is the universal gas constant. We calculate as follows:
PV = nRT
n = PV / RT
n = (18.6/760) (7.80) / 0.08205 ( 21 + 273.15)
n = 0.0079 mol
Mass = 0.0079 mol ( 18.02 g / mol ) = 0.1425 g H2
Lyman Series Working Formula:
1/λ = RH (1-(1/n^2))
Given:
n = 6
RH = Rydberg's constant = 1.0968x10^7 m^-1
c = speed of light = 3x10^8 m/s
Required:
Frequency (Hertz or cycles per second)
Solution:
To solve for the wavelength λ, we substitute the given in the working formula
1/λ = RH (1-(1/n^2))
1/λ = 1.0968x10^7 m^-1 (1-(1/6^2))
λ = 0.0000000938 m or 93.8 nm
To get the frequency, we will use the formula below.
f = c/λ
We then substitute c or the speed of light,
f = (3x10^8 m/s) / 0.0000000938 m
Therefore,
f = 3.2x10^15 s^-1
<em>ANSWER: Frequency = </em><em /><em>3.2x10^15 s^-1</em>
Answer:
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Alcohol-related diseases frequently cause low Mg+ levels.
- Mg+ deficiencies must be treated before potassium (K+) deficiencies.
- Mg+ deficiencies often result in low serum potassium (K+)
- Mg++ levels present similarly to calcium (Ca++) levels in the blood.
- Vomiting is not generally seen as a major cause of Mg+ loss
Answer: The correct answer is "B" two bonding domains(or bonding pairs) or two non bonding domains(or lone pairs)
Explanation:
Molecular geometry/structure is a three dimensional shape of a molecule. It is basically an arrangement of atoms in a molecule.It is determined by the central atom, its surrounding atoms and electron pairs.According to VSEPR theory, there are 5 basic shapes of a molecule: linear, trigonal planar, tetrahedral, trigonal bipyramidal and octahedral.
A)Four bonding domains and zero non bonding domains: shape is tetrahedral and bond angle is 109.5°
B)Two bonding domains and two non bonding domains(lone pairs): shape is bent and bond angle is 104.5°
C)Three bonding domains and one non bonding domain: shape is trigonal pyramidal and bond angle is 107°
D)Two bonding domain and zero non bonding domain: shape is linear and bond angle is 107°
E)Two bonding domain and one non bonding domain: bent shape and bond angle is 120°
F)Three bonding domains and zero nonbonding domain: shape is trigonal planar and bond angle is 120°
Hence Two bonding domains and two non bonding domains have the smallest bond angle.
Answer:
4.16L
Explanation:
From the question given, we obtained the following data:
Molarity = 0.225 M
Number of mole of KI = 0.935mole
Volume =?
Molarity = mole / Volume
Volume = mole /Molarity
Volume = 0.935/0.225
Volume = 4.16L
Therefore, 4.16L of KI is needed.
