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2 years ago

You are given a cube of pure copper when you calculate the density using

Chemistry

1 answer:

lara [203]2 years ago

5 0

Answer:

2.01% to the nearest hundredth.

Explanation:

Percent error =[ (8.96-8.78) / 8.96]* 100

= 0.020089 * 100

= 2.0089 %

You might be interested in

Jordan's puppy has a mass of 5480 milligrams , what is the puppy's mass in grams ?

Vesnalui [34]

5480milligrams=5.47×10^1grams

5480×10^-2

5.480×10^(-2+3)

5.48×10^1grams

5 0

3 years ago

Calculate the ph of a dilute solution that contains a molar ratio of potassium acetate to acetic acid (pka ???? 4.76) of (a) 2:1

givi [52]

According to Hasselbach-Henderson equation:

$pH=pK_{a}+log\frac{[A^{-}]}{[HA]}$

Here, $[A^{-}]$ is concentration of conjugate base and [HA] is concentration of acid.

In the given problem, conjugate base is $CH_{3}COOK$ and acid is $CH_{3}COOH$ thus, Hasselbach-Henderson equation will be as follows:

$pH=pK_{a}+log\frac{[CH_{3}COOK]}{[CH_{3}COOH]}$ ...... (1)

(a) Ratio of concentration of potassium acetate and acetic acid is 2:1 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=2$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{2}{1}=5.06$

Therefore, pH of solution is 5.06.

(b) Ratio of concentration of potassium acetate and acetic acid is 1:3 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=\frac{1}{3}$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{1}{3}=4.28$

Therefore, pH of solution is 4.28.

(c)Ratio of concentration of potassium acetate and acetic acid is 5:1 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=\frac{5}{1}$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{5}{1}=5.45$

Therefore, pH of solution is 5.45.

(d) Ratio of concentration of potassium acetate and acetic acid is 1:1 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=1$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{1}{1}=4.76$

Therefore, pH of solution is 4.76.

(e) Ratio of concentration of potassium acetate and acetic acid is 1:10 thus,

$\frac{[CH_{3}COOK]}{[CH_{3}COOH]}=\frac{1}{10}$

Also, $pK_{a}=4.76$

Putting the values in equation (1),

$pH=4.76+log\frac{1}{10}=3.76$

Therefore, pH of solution is 3.76.

4 0

2 years ago

If 100 ml of a 0.5 M HCI Solution is diluted with water to 1000ml, what is the new concetration?

Vesna [10]

Answer:

$0.05\ \text{M HCl}$

Explanation:

$V_1$ = Initial volume = 100 mL

$V_2$ = Final volume = 1000 mL

$M_1$ = Initial concentration = 0.5 M

$M_2$ = Final concentration

We have the relation

$\dfrac{M_1}{M_2}=\dfrac{V_2}{V_1}\\\Rightarrow M_2=M_1\dfrac{V_1}{V_2}\\\Rightarrow M_2=0.5\times \dfrac{100}{1000}\\\Rightarrow M_2=0.05\ \text{M HCl}$

The new concentration is $0.05\ \text{M HCl}$ .

3 0

3 years ago

Which condition is indicated by nervous tension, mood swings, headaches, bloating, and irritability?

butalik [34]

The best and most correct answer among the choices provided by your question is the third choice or letter C.

Premenstrual syndrome (PMS) has a wide variety of symptoms, including mood swings, tender breasts, food cravings, fatigue, irritability and depression. It's estimated that as many as 3 of every 4 menstruating women have experienced some form of premenstrual syndrome. Symptoms tend to recur in a predictable pattern.

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!

4 0

3 years ago

El NaCI corresponde a un elemento?

Schach [20]

Answer:

Sodio (Na), elemento químico del grupo de los metales alcalinos (Grupo 1 [Ia]) de la tabla periódica. El sodio es un metal blanco plateado muy suave. El sodio es el metal alcalino más común y el sexto elemento más abundante en la Tierra, y comprende el 2,8 por ciento de la corteza terrestre.

Explanation:

Espero que esto ayude a marcar el MÁS CEREBRAL !!!

7 0

3 years ago