Solution:
The molecular formula is PbSO₄, indicating lead sulfate
Option c.
Explanation:
The percentage makeup shows that in 100 g of this compound, there are:
68.3 g of Pb, 10.6 g of S, and (100 - 68.3 - 10.6) = 21.1 g of O
To find the moles of each element, we divide by their molar masses:
68.3 g Pb / 207.2 g/mol = 0.329 moles Pb
10.6 g S / 32.06 g/mol = 0.331 moles S
21.1 g O / 16 g/mol = 1.32 moles O
Next, we find the mole ratio by dividing each by the smallest number of moles:
0.329 / 0.329 = 1 Pb
0.331 / 0.329 = 1 S
1.32 / 0.329 = 4 O
Thus, the molecular formula is PbSO₄, representing lead sulfate.
Answer:
vHe / vNe = 2.24
Explanation:
To determine the velocity of an ideal gas, one should apply the formula:
v = √3RT / √M
In this equation, R represents the gas constant (8.314 kgm²/s²molK); T refers to temperature, and M indicates the molar mass of the gas (4x10⁻³kg/mol for helium and 20.18x10⁻³ kg/mol for neon). Hence:
vHe = √3×8.314 kgm²/s²molK×T / √4x10⁻³kg/mol
vNe = √3×8.314 kgm²/s²molK×T / √20.18x10⁻³kg/mol
The ratio simplifies to:
vHe / vNe = √3×8.314 kgm²/s²molK×T / √4x10⁻³kg/mol / √3×8.314 kgm²/s²molK×T / √20.18x10⁻³kg/mol
vHe / vNe = √20.18x10⁻³kg/mol / √4x10⁻³kg/mol
vHe / vNe = 2.24
I hope it assists you!
684 kcal. One mole of glucose weighs roughly 180g. Given that 1g of glucose releases 3.8 kcal, we calculate for 1 mole of glucose: 180g -> 180g * 3.8 kcal/g = 684 kcal.
A indicates the power lines are what truly conducts (or transmits) the power.
Options B or E are incorrect, as wood is not a good conductor. That's why it's commonly used in homes to retain heat (which comes from electricity), preventing it from escaping.
Option C is also not correct since rubber, similarly, is a poor conductor. Like wood, it acts as an insulator, not transmitting heat (or electricity). This is why rubber gloves are utilized during electrical work.
Option D is valid—most metals are excellent electricity conductors. For instance, copper pans are efficient in cooking because copper effectively conducts heat. Being a metal, this is also why wire cutters have rubber grips; it isolates the user from potential electric shock from the conductive metal. The rubber serves as a barrier to protect against electrocution when handling wires or electricity.
