How does the number of molecules in one mole of carbon dioxide compare with the number of molecules in one mole of water?

Why do the elements in a group all behave similarly

Svetradugi [14.3K]

Answer:

See the explanation below, please.

Explanation:

The elements of the periodic table that belong to the same group (each column) have similar physical and chemical properties. This is because they have the same number of electrons in their last electronic layer.

Example of electronic configuration of elements of GROUP IA:

Hydrogen: 1s ^ 1

Lithium: 1s ^ 2 2s ^ 1

6 0

3 years ago

A mileage test is conducted for a new car model. Thirty randomly selected cars are driven for a month and the mileage is measure

Leni [432]

Answer: $(27.81,\ 29.39)$

Explanation:

Given : Sample size : n= 30 , it means it is a large sample (n≥ 30), so we use z-test .

Significance level : $\alpha: 1-0.95=0.05$

Critical value: $z_{\alpha/2}=1.96$

Sample mean : $\overline{x}=28.6$

Standard deviation : $\sigma=2.2$

The formula to find the confidence interval is given by :-

$\overline{x}\pm z_{\alpha/2}\dfrac{\sigma}{\sqrt{n}}$

i.e. $28.6\pm (1.96)\dfrac{2.2}{\sqrt{30}}$

i.e. $28.6\pm 0.787259889321$

$\approx28.6\pm 0.79=(28.6-0.79,28.6+0.79)=(27.81,\ 29.39)$

Hence, the 95% confidence interval for the mean mpg in the entire population of that car model = $(27.81,\ 29.39)$

4 0

3 years ago

If a 0.320 mM solution of MnO41- has an absorbance of 0.480 at 525 nm in a 1.000 cm cell. What is the concentration of a MnO41-

larisa [96]

Answer:

Hence the concentration of a MnO41- solution that has absorbance of 0.490 in the same cell at that wavelength is 0.3266.

Explanation:

Now A = el, el=const

Then,

$A2 / A1 = C2/ C1\\\\0.49/ 0.48 = C2 / 0.32\\\\C2 = 0.3266$

3 0

3 years ago

How are water molecules able to weakly bond to one another with hydrogen bonds?

zvonat [6]

C. slight opposite charges

Explanation: opposites attract

8 0

3 years ago

The nonvolatile, nonelectrolyte DDT , C14H9Cl5 (354.5 g/mol), is soluble in benzene, C6H6. Calculate the osmotic pressure (in at

Ainat [17]

Step 1

The osmotic pressure is calculated as follows:

$\begin{gathered} \pi\text{ = C x R x T} \\ C\text{ = molarity = }\frac{moles\text{ of solute}}{Volume\text{ of solution \lparen L\rparen}} \\ R\text{ = 0.082 }\frac{atmxL}{mol\text{ x K}} \end{gathered}$

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Step 2

<em>Information provided:</em>

The mass of solute = 13.6 g

Volume of solution = 251 mL

Absolute temperature = T = 298 K

The molar mass of solute = M = 354.5 g/mol

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Step 3

Procedure:

1 L = 1000 mL => Volume = 251 mL x (1 L/1000 mL) = 0.251 L

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C = moles of solute/volume of solution (L)

C = mass of solute/(molar mass x Volume (L))

C = 13.6 g/(354.5 g/mol x 0.251 L)

C = 0.153 mol/L

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π = C x R x T

π = 0.153 mol/L x 0.082 atm L/mol K x 298 K

π = 3.74 atm

Answer: π = 3.74 atm

4 0

1 year ago