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3 years ago

Which of the following statements is true about the periodic table.

Chemistry

2 answers:

mixer [17]3 years ago

8 0

Answer:

In this question, the statement 2 is correct and true while other statements are incorrect.

Explanation:

The properties of an element can be easily predicted from the periodic table. We can find out the atomic number of the element from the periodic table. According to the periodic table, the properties of element is dependent on the atomic number of the element. The behavior of element during a chemical reaction can be predicted from the atomic number.

Element can only belong to one group at a time. Hence, statement (3) is not correct.

The periodic table is still used by scientists for predicting the properties. Hence, it is not outdated. Statement (1) is not correct.

Statement (2) is correct

kodGreya [7K]3 years ago

5 0

Answer: 2

Explanation:

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The concentration of a saturated BaCl2 solution is 1.75 M (mol/liter) and the concentration of a saturated Na2SO4 solution is 2.

Kitty [74]

Answer:

a) The theoretical yield is 408.45g of $BaSO_{4}$

b) Percent yield = $\frac{realyield}{408.45g}*100$

Explanation:

1. First determine the numer of moles of $BaCl_{2}$ and $Na_{2}SO_{4}$ .

Molarity is expressed as:

M= $\frac{molessolute}{Lsolution}$

- For the $BaCl_{2}$

M= $\frac{1.75molesBaCl_{2}}{1Lsolution}$

Therefore there are 1.75 moles of $BaCl_{2}$

- For the $Na_{2}SO_{4}$

M= $\frac{2.0moles[tex]Na_{2}SO_{4}$ }{1Lsolution}[/tex]

Therefore there are 2.0 moles of $Na_{2}SO_{4}$

2. Write the balanced chemical equation for the synthesis of the barium white pigment, $BaSO_{4}$ :

$BaCl_{2}+Na_{2}SO_{4}=BaSO_{4}+2NaCl$

3. Determine the limiting reagent.

To determine the limiting reagent divide the number of moles by the stoichiometric coefficient of each compound:

- For the $BaCl_{2}$ :

$\frac{1.75}{1}=1.75$

- For the $Na_{2}SO_{4}$ :

$\frac{2.0}{1}=2.0$

As the $BaCl_{2}$ is the smalles quantity, this is the limiting reagent.

4. Calculate the mass in grams of the barium white pigment produced from the limiting reagent.

$1.75molesBaCl_{2}*\frac{1molBaSO_{4}}{1molBaCl_{2}}*\frac{233.4gBaSO_{4}}{1molBaSO_{4}}=408.45gBaSO_{4}$

5. The percent yield for your synthesis of the barium white pigment will be calculated using the following equation:

Percent yield = $\frac{realyield}{theoreticalyield}*100$

Percent yield = $\frac{realyield}{408.45g}*100$

The real yield is the quantity of barium white pigment you obtained in the laboratory.

7 0

3 years ago

How many moles of aspartame are present in 1.00 mg of aspartame?

Diano4ka-milaya [45]

Answer:- There are $3.40*10^-^6$ moles.

Solution:- It is a unit conversion problem where we are asked to convert mg of aspartame to moles. Aspartame is $C_1_4H_1_8N_2O_5$ and it's molar mass is 294.31 grams per mole.

mg are converted to grams and then the grams are converted to moles as:

$1.00mg Aspartame(\frac{1g}{1000mg})(\frac{1mole}{294.31g})$

= $3.40*10^-^6$ moles of aspartame

So, there would be $3.40*10^-^6$ moles of aspartame in 1.00 mg of it.

3 0

4 years ago

A force of 129,000 N is accelerating a car at 84 m/s/s<br> what’s the mass of the car?

Marianna [84]

M=f/a m=129000N/84m/s/s=1535.714286kg/m/s/s

5 0

2 years ago

If 4.5 moles of AlCl3 were made, how many moles of CuCl2 were used?

Troyanec [42]

Answer:

6.75 moles of CuCl₂ were used

Explanation:

Given data:

Number of moles of AlCl₃ formed = 4.5 mol

Number of moles of CuCl₂ used = ?

Solution:

Chemical equation:

3CuCl₂ + 2Al → 2AlCl₃ + 3Cu

Now we will compare the moles of CuCl₂ and AlCl₃

AlCl₃ : CuCl₂

2 : 3

4.5 : 3/2×4.5 = 6.75

6.75 moles of CuCl₂ were used.

7 0

2 years ago

The stability of atomic nuclei is related to the

Gekata [30.6K]

Ratio of neutrons & protons .

6 0

3 years ago