The electrons in the outermost energy level of an atom that influence how an element will react with other substances

Lead forms two compounds with oxygen. One contains 2.98g of lead and 0.461g of oxygen. The other contains 9.89g of lead and 0.76

aliina [53]

The given question is incomplete, the complete question is:

Lead forms two compounds with oxygen. One contains 2.98g of lead and 0.461g of oxygen. The other contains 9.89g of lead and 0.763g of oxygen. For a given mass of oxygen, what is the lowest whole-number mass ratio of lead in the two compounds that combines with a given mass of oxygen?

Answer:

The lowest whole-number mass ratio in the two compounds is 1:2.

Explanation:

There is a need to find the mole ratio between lead and oxygen atoms in order to find the whole-number mass ratio of lead in the two compounds. In the first compound, the given mass of lead is 2.98 grams, the molar mass of lead is 207.2 gram per mole.

The no. of moles can be determined by using the formula,

moles = mass/molecular mass

moles = 2.98 g/207.2 g/mol

= 0.0144 moles

The mass of oxygen in the compound I is 0.461 grams, the molecular mass of oxygen is 16 gram per mol.

moles = 0.461 g /16 g/mol

= 0.0288 moles

The ratio between the lead and oxygen in the compound I is 0.0144/0.0288 = 1:2

On the other hand, in the compound II, the mass of lead given is 9.89 grams, therefore, the moles of lead in compound II is,

moles = 9.89 g / 207.2 g/mol

= 0.0477 moles

The mass of oxygen given in compound II is 0.763 grams, the moles of oxygen present in the compound II is,

moles = 0.763 g / 16 g

= 0.0477 moles

The ratio between the lead and oxygen in the compound II is, 0.0477 moles lead /0.0477 moles oxygen = 1:1

Hence, of the two compounds, the lowest ratio is found in the compound I, that is, 1:2.

4 0

3 years ago

Linda performed the following trials in an experiment. Trial 1: Heat 30.0 grams of water at 0 °C to a final temperature of 40.0

nexus9112 [7]

Answer: The correct answer is Option b.

Explanation:

To calculate the amount of heat absorbed or released, we use the following equation:

$q=mc\Delta T$ .....(1)

where, q = amount of heat absorbed or released.

m = mass of the substance

c = heat capacity of water = 4.186 J/g ° C

$\Delta T$ = Change in temperature

For Trial 1:

We are given:

$m=30g\\\Delta T=[40-0]^oC=40^oC\\q=?J$

Putting values in equation 1, we get:

$q=30g\times 4.186J/g^oC\times 40^oC$

q = 5023.2 J

For trial 2:

We are given:

$m=40g\\\Delta T=[40-30]^oC=10^oC\\q=?J$

Putting values in equation 1, we get:

$q=40g\times 4.186J/g^oC\times 10^oC$

q = 1674.4 J

Heat gained by Trial 1 than trial 2 = $(5023.2-1674.4)J=3347J$

Hence, the amount of heat gained in Trial 1 about 3347 J more than the heat released in Trial 2.

Thus, the correct answer is Option b.

4 0

3 years ago

) What parts of pizzly resemble that of a grizzly bear?

user100 [1]

Answer:

Animal was shot in Nunavut, Canada earlier this month by hunters. It resembles a polar bear but has claws and brown paws of a grizzly bear. Experts claim the 'pizzly' or 'grolar' bear is a hybrid between the two. DNA tests revealed it was actually a blonde haired grizzly bear

Explanation:

6 0

3 years ago

An experiment was conducted to determine the density of a rock sample. The table shows a partial record of the experiment.

mart [117]

Answer: the density of the rock

55.91g/ml

Explanation:

The density of the rock after it had being placed in the cylinder of water so the calculation should look like this:

Volume of water substract the mass of the rock:

And that is 142.5 ml - 86.59g =

Answer 55.91 g/ml

So the density of the rock is 55.91g/ml

5 0

2 years ago

How many liters would you need to make a 2 M solution if you have 3 mol of Sodium Hydroxide

Kipish [7]

Answer:

A 1 molar (M) solution will contain 1.0 GMW of a substance dissolved in water to make 1 liter of final solution. Hence, a 1M solution of NaCl contains 58.44 g.

Explanation:

6 0

3 years ago