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3 years ago

What is the atomic number of arsenic (As)? O A. 33 O B. 15 C. 75 D. 4 SUB

Chemistry

2 answers:

mr_godi [17]3 years ago

6 0

The atomic number of arsenic is 33

stepan [7]3 years ago

5 0

Answer:

Explanation:

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Identifying polar regions within molecules is a very useful skill for chemists that helps us to think about the strength of inte

Ilia_Sergeevich [38]

bond in the acetic acid molecule is the most polar c. c=o bond
which bond in the methyl amine molecule is the most polar c. n–h bond

4 0

3 years ago

Which of the following is not the same as 2.97 milligrams?

Len [333]

Hi There!!!!!!

Which of the following is not the same as 2.97 milligrams?A)0.297 cg
B)0.00297 g
C) 0.0000297 KG

Answer:0.00297 g

5 0

2 years ago

Read 2 more answers

During a titration the following data were collected. A 50.0 mL portion of an HCl solution was titrated with 0.500 M NaOH; 200.

Travka [436]

Answer: The mass of HCl present in 500 mL of acid solution is 36.5 grams

Explanation:

To calculate the concentration of acid, we use the equation given by neutralization reaction:

$n_1M_1V_1=n_2M_2V_2$

where,

$n_1,M_1\text{ and }V_1$ are the n-factor, molarity and volume of acid which is HCl

$n_2,M_2\text{ and }V_2$ are the n-factor, molarity and volume of base which is NaOH.

We are given:

$n_1=1\\M_1=?M\\V_1=50.00mL\\n_2=1\\M_2=0.500M\\V_2=200.mL$

Putting values in above equation, we get:

$1\times M_1\times 50.00=1\times 0.500\times 200\\\\M_1=\frac{1\times 0.500\times 200}{1\times 50.00}=2M$

To calculate the mass of solute, we use the equation used to calculate the molarity of solution:

$\text{Molarity of the solution}=\frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (in mL)}}$

Molar mass of HCl = 36.5 g/mol

Molarity of solution = 2 M

Volume of solution = 500 mL

Putting values in above equation, we get:

$2mol/L=\frac{\text{Mass of solute}\times 1000}{36.5g/mol\times 500}\\\\\text{Mass of solute}=\frac{2\times 36.5\times 500}{1000}=36.5g$

Hence, the mass of HCl present in 500 mL of acid solution is 36.5 grams

4 0

2 years ago

If 2.5L of solution is diluted to prepare 1.7L of a 0.8M solution, what was the original concentration?

mamaluj [8]

Answer:

0.544 M

Explanation:

First find the moles in the final solution

0.8 mols/L *1.7L

1.36 mols

so there is 1.36 mols in 2.5L

concentration will be 1.36/2.5

0.544 M

5 0

2 years ago

Hot water enters a double-pipe counter-flow water-to-oil heat exchanger at 220°7 and leaves a 100°F. Oil enters at 70°F and leav

il63 [147K]

Answer:

Oil has the smaller heat capacity. The effectiveness of the heat exchanger is 0.80.

Explanation:

Part 1:

In order to know which fluid has the smaller heat capacity we need to consider the heat equation below:

Q = CΔT, where Q is the heat exchanged, C is the heat capacity and ΔT is the variation in temperature.

As the heat exchange is the same for both fluids, the smaller the temperature variation, the smaller the heat capacity.

Water: ΔT = 120 °F

Oil: ΔT = 80 °F

Therefore, oil is the fluid with the smallest heat capacity.

Part 2:

The effectiveness of a counter-flow heat exchanger is given by the equation bellow:

$E = \frac{Th1 - Th2}{Th1 - Tc1} \\$

Th1: initial temperature of the hot fluid

Th2: final temperature of the hot

Tc1: initial temperature of the cold fluid

$E = \frac{220 - 100}{220 - 70} \\E = 0.8$

7 0

3 years ago