How many valence electrons are in Tr2-

Chromium (III) forms a complex with diphenylcarbazide whose molar absorptivity is 4.17x104 at 540 nm.

son4ous [18]

Answer:

3.00 cm

Explanation:

The absorbance can be expressed using Beer-Lambert's law:

A = ε*b*c

Where ε is a constant for each compound, b is the optical path, and c is the molar concentration of the compound.

Now we match the absorbance values for both solutions, because we want the absorbance value to be the same for both solutions:

A = ε * 1.00 cm * 7.68x10⁻⁶M = ε * b * 2.56x10⁻⁶ M

And solve for b:

ε * 1.00 cm * 7.68x10⁻⁶M = ε * b * 2.56x10⁻⁶ M

1.00 cm * 7.68x10⁻⁶M = b * 2.56x10⁻⁶ M

b = 3.00 cm

5 0

3 years ago

Which of the following has the electron configuration [ar] 4s23d5 ?

nignag [31]

Answer:

Mn Manganese

Explanation:

5 0

3 years ago

Measure that affects the thermal energy of matter but not it's temperature.

jenyasd209 [6]

Answer: mass

Explanation:

6 0

3 years ago

A certain compound of bromine and fluorine is used to make UF6, which is an important chemical in the processing and reprocessin

Aleksandr [31]

Answer: The empirical formula is $BrF_3$

Explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of Br= 58.37 g

Mass of F = (100-58.37) = 41.63 g

Step 1 : convert given masses into moles.

Moles of Br= $\frac{\text{ given mass of Br}}{\text{ molar mass of Br}}= \frac{58.37g}{80g/mole}=0.73moles$

Moles of F = $\frac{\text{ given mass of H}}{\text{ molar mass of H}}= \frac{41.63g}{19g/mole}=2.2moles$

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For Br = $\frac{0.73}{0.73}=1$

For F = $\frac{2.2}{0.7}=3$

The ratio of Br: F= 1 : 3

Hence the empirical formula is $BrF_3$

8 0

3 years ago

Question 1 (True/False Worth 2 points) (04.03 LC) When Pb and AlCl3 react together, lead (Pb) can replace aluminum (Al) in the c

aivan3 [116]

Answer:

For 1: The correct answer is false.

For 2: The correct answer is $Na_3PO_4+3KOH\rightarrow 3NaOH + K_3PO_4$ , because K retains the same charge throughout the reaction.

For 3: The correct answer is $Zn+H_2SO_4\rightarrow ZnSO_4 + H_2$

For 4: The correct answer is a single replacement reaction takes place because sodium is more reactive than hydrogen.

For 5: The correct answer is False.

For 6: The correct answer is it is a single replacement reaction, and the cations in the two ionic compounds are different.

Explanation:

For 1:

This type or reaction is based on the reactivity series. If the metal which lies above in the series will replace the metal which lies below in the series easily.

From the reactivity table attached below, we know that lead lies below in the series to Aluminium and hence, it will not replace in the reaction.

$Pb+AlCl_3\rightarrow \text{No reaction}$

Hence, the correct answer is False.

For 2:

A balanced equation is defined as the equation in which there are same number of atoms present on the reactant side and the product side.

The balanced equation always follow Law of Conservation of Mass.

So, from the given options, the below equation is the balanced equation because K retains the same charge throughout the reaction.

$Na_3PO_4+3KOH\rightarrow 3NaOH + K_3PO_4$

For 3:

A single displacement reaction is a type of chemical reaction in which one element replaces another element in a chemical reaction. The element which is more reactive will replace the less less reactive element.

This is explained by reactivity series as the metal which lies above in the series will replace the metal which lies below in the series easily. From the given equations, the equation which is a type of single displacement reaction is:

$Zn+H_2SO_4\rightarrow ZnSO_4 + H_2$

$Ba(OH)_2+H_2SO_4\rightarrow BaSO_4 + 2H_2O$ : This equation is a type of double displacement reaction.

$2Mg+O_2\rightarrow 2MgO$ : This equation is a type of combination reaction.

$H_2O+CO_2\rightarrow H_2CO_3$ : This equation is a type of combination reaction.

For 4:

A single displacement reaction is a type of chemical reaction in which one element replaces another element in a chemical reaction.

$A+BC\rightarrow AC+B$

A double displacement reaction is a type of chemical reaction in which exchange of ins takes place.

$AB+CD\rightarrow AD+BC$

In the question, it is asked that sodium metal is reacting with water to produce hydrogen gas and sodium hydroxide. This reaction is a type of single displacement reaction because sodium is more reactive than hydrogen as shown in the reactivity series.

$2Na+2H_2O\rightarrow H_2+2NaOH$

For 5:

A single displacement reaction is a type of chemical reaction in which one element replaces another element in a chemical reaction. This reaction will not follow when an element replaces similar element.

Hence, the statement is False.

For 6:

For the reaction:

$\text{Metal + Ionic compound}\rightarrow \text{Metal + Ionic compound}$

It is a type single replacement reaction as the cations in the two ionic compounds are different.

For Example:

$3Na+AlCl_3\rightarrow 3NaCl+Al$

Where, Sodium and Aluminium are the cations and chlorine is an anion.

6 0

4 years ago

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