Answer:
If the gases are at equal pressure, the gas at higher temperature will be less dense. If the gases are at the same temperature, the gas at higher pressure will be more dense. If two gases of different molecular weights are at the same pressure and temperature in containers of equal size, then the high molecular weight gas will be more dense.
Explanation:
The density of a gas decreases with increase in temperature at constant pressure. This is because, when a gas is heated, the kinetic energy of its molecules increases, the molecules move faster, bump into each other, and spread apart and therefore the volume of the gas increases. Since the gas molecules are now more spaced out, the density of the gas decreases.
The density of a gas has a direct relationship with pressure. The density of a gas increases with increases in pressure at constant temperature. This is because, when the pressure of a gas is increased, the space between the molecules decreases as they are forced to become more crowded together, as such the volume ofmthe gas decreases. The density of the gas will then increase.
The molecular weight of a gas is directly proportional to its density. Hence, gases of low molecular weight has lower densities while gases of high molecular weight have higher densities.
Hence, If the gases are at equal pressure, the gas at higher temperature will be less dense. If the gases are at the same temperature, the gas at higher pressure will be more dense. If two gases of different molecular weights are at the same pressure and temperature in containers of equal size, then the high molecular weight gas will be more dense.
Answer:
The molarity of sodium chloride in sea water is 0.479 M
Explanation:
Step 1: Data given
Mass of NaCl = 28.0 grams
Molar mass NaCl = 58.44 g/mol
Step 2: Calculate moles
Moles NaCl = mass NaCl / molar mass NaCl
Moles NaCl = 28.0 grams / 58.44 g/mol
Moles NaCl = 0.479 moles
Step 3: Calculate molarity NaCl in sea water
Molarity = moles / volume
Molarity NaCl = 0.479 moles / 1L
Molarity of NaCl in sea water = 0.479 mol/L = 0.479 M
The molarity of sodium chloride in sea water is 0.479 M
Answer:f
- First option: <em>the melting temperature is relatively high.</em>
Explanation:
You can look at the melting temperature at any table that summarizes the main properties of this compound, <em>potassium chloride</em>.
Such melting point is 770 °C, which is relatively high.
<u>Why is this?</u>
Potassium chloride is a ionic compound formed by the cations of potassium, K⁺, and the chloride anions, Cl⁻. Its unit formula is KCl.
The ionic bond between K and Cl is possible because each K atom is able to yield its valence electron to one Cl atom which has 7 valence electrons.
Then, the K atoms become positive ions (cations) K⁺, while Cl atoms become negative ions (Cl⁻).
These two ions with opposite charge are bonded by the force of electrostatic attraction. This is a ionic bond.
<em>Melting point</em>, so as boiling point along with other physical properties, depends on the attraction force between the atoms.
Hence, since the attrative forces between the ions are relatively strong, the <em>melting point</em> of the ionic compounds, such as potassium chloride, are <em>relatively high.</em>
Answer:
The heat capacity of the calorimeter is 5.11 J/g°C
Explanation:
Step 1: Given data
50.0 mL of water with temperature of 80.0 °C
Specific heat capacity of water = 4.184 J/g°C
Consider the density of water = 1g/mL
50.0 mL of water in a calorimeter at 20.0 °C
Final temperature = 47.0 °C
Step 2: Calculate specific heat capacity of the water in calorimeter
Q = Q(cal) + Q(water)
Q(cal) = mass * C(cal) * ΔT
Qwater = mass * Cwater * ΔT
Qcal = -Qwater
mass(cal) * C(cal) * ΔT(cal) = mass(water) * C(water) * ΔT(water)
50 grams * C(cal) * (47.0 - 20.0) =- 50grams * 4.184 J/g°C * (47-80)
1350 * C(cal) = 6903.6
C(cal) = 5.11 J/g°C
The heat capacity of the calorimeter is 5.11 J/g°C
N2 + 3 H2 >> 2 NH3
moles NH3 = 11.50 g /17.0307 g/mol=0.6753
the ratio between H2 and NH3 is 3 : 2
moles H2 needed = 0.6753 x 3/2 =1.013
mass H2 = 1.013 mol x 2.106 g/mol=2.042 g
