True or false? Elements are impure, meaning that different samples of an element have different properties.

4. Quando se obtém a potência máxima da célula, o valor indicado no amperímetro, na unidade SI, está no intervalo: (A) [3,1; 3,2

Annette [7]

Answer:i dont speak english

Explanation:

sorry

8 0

2 years ago

The equilibrium constant, Kc, for the following reaction is 5.10×10-6 at 548 K. NH4Cl(s) NH3(g) + HCl(g) Calculate the equilibri

levacccp [35]

Answer: The equilibrium concentration of HCl is $2.26\times 10^{-3}M$

Explanation:

We are given:

Moles of $NH_4Cl(s)$ = 0.564 moles

Volume of vessel = 1.00 L

Molarity is calculated by using the equation:

$\text{Molarity}=\frac{\text{Number of moles}}{\text{Volume of solution (in L)}}$

Molarity of $NH_4Cl=\frac{0.564}{1}=0.564M$

The given chemical equation follows:

$NH_4Cl(s)\rightleftharpoons NH_3(g)+HCl(g)$

Initial: 0.564

At eqllm: 0.564-x x x

The expression of $K_c$ for above equation follows:

$K_c=[NH_3][HCl]$

The concentration of pure solid and pure liquid is taken as 1.

We are given:

$K_c=5.10\times 10^{-6}$

Putting values in above equation, we get:

$5.10\times 10^{-6}=x\times x\\\\x=2.26\times 10^{-3}M,-2.26\times 10^{-3}M$

Negative sign is neglected because concentration cannot be negative.

So, $[HCl]=2.26\times 10^{-3}M$

Hence, the equilibrium concentration of HCl is $2.26\times 10^{-3}M$

5 0

3 years ago

The measurement 1.00540 g contains significant figures. * 10 3 4 5 O 6

antiseptic1488 [7]

It contains 6 sig figs

4 0

3 years ago

0.40 L of HNO3 is titrated to equivalence using 0.18 L of 0.1 M NaOH. What is the concentration of the HNO3 ?

e-lub [12.9K]

This problem is providing us with the volume of nitric acid that is titrated with 0.18 L of 0.1-M sodium hydroxide and asks for the concentration of the acid. At the end, the result turns out to be 0.045M, according to the following.

<h3>Acid-base titrations:</h3>

In chemistry, acid-base titrations allow us to quantify the volume or concentration of an acid or base via the following equation:

$M_AV_A=M_BV_B$

Where the subscript A stands for the acid and B for the base; which means one can calculate any of the variables there by knowing the other three. This equation is based on the balanced neutralization chemical equation, which takes place between the acid and the base.

Thus, we can write the reaction between NaOH and HNO3 as:

$HNO_3+NaOH\rightarrow NaNO_3+H_2O$

In such a way, we can solve for the concentration of the acid as shown below:

$M_A=\frac{M_BV_B}{V_A} \\\\M_A=\frac{0.1M*0.18L}{0.40L} \\\\M_A=0.045M$

Learn more about titration: brainly.com/question/25485091

3 0

1 year ago

How much in grams, does 5.68 x 1022 formula units of potassium dichromate weigh?

Alexxx [7]

Answer:

Explanation:

The molecular formula for Potassium Dichromate is K2Cr2O7. The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles Potassium Dichromate, or 294.1846 grams.

Note that rounding errors may occur, so always check the results.

8 0

2 years ago