Dribbling a basketball harder into the floor makes it bounce higher is an example of what newton's law?

A 7.06% aqueous solution of sodium bicarbonate has a density of 1.19g/mL at 25°C what is the molarity and molality of the soluti

lilavasa [31]

c = 1.14 mol/L; b = 1.03 mol/kg

Molar concentration

Assume you have 1 L solution.

Mass of solution = 1000 mL solution × (1.19 g solution/1 mL solution)

= 1190 g solution

Mass of NaHCO3 = 1190 g solution × (7.06 g NaHCO3/100 g solution)

= 84.01 g NaHCO3

Moles NaHCO3 = 84.01 g NaHCO3 × (1 mol NaHCO3/74.01 g NaHCO3)

= 1.14 mol NaHCO3

c = 1.14 mol/1 L = 1.14 mol/L

Molal concentration

Mass of water = 1190 g – 84.01 g = 1106 g = 1.106 kg

b = 1.14 mol/1.106 kg = 1.03 mol/kg

5 0

3 years ago

Read 2 more answers

What principal quantum number refers to:

docker41 [41]

The principle quantum number "n" represents the relative overall energy of each orbital, and the energy of each orbital increases as the distance from the nucleus increases. The sets of orbitals with the same "n" value are often referred to as electron shells or energy levels.

4 0

3 years ago

What is the percent yield of a reaction in which 51.5 g of tungsten(VI) oxide (WO3) reacts with excess hydrogen gas to produce m

Rus_ich [418]

Answer:

The percent yield of a reaction is 48.05%.

Explanation:

$WO_3+3H_2\rightarrow W+3H_2O$

Volume of water obtained from the reaction , V= 5.76 mL

Mass of water = m = Experimental yield of water

Density of water = d = 1.00 g/mL

$M=d\times V = 1.00 g/mL\times 5.76 mL=5.76 g$

Theoretical yield of water : T

Moles of tungsten(VI) oxide = $\frac{51.5 g}{232 g/mol}=0.2220 mol$

According to recation 1 mole of tungsten(VI) oxide gives 3 moles of water, then 0.2220 moles of tungsten(VI) oxide will give:

$\frac{3}{1}\times 0.2220 mol=0.6660 mol$

Mass of 0.6660 moles of water:

0.666 mol × 18 g/mol = 11.988 g

Theoretical yield of water : T = 11.988 g

To calculate the percentage yield of reaction , we use the equation:

$\%\text{ yield}=\frac{\text{Experimental yield}}{\text{Theoretical yield}}\times 100$

$=\frac{m}{T}\times 100=\frac{5.76 g}{11.988 g}\times 100=48.05\%$

The percent yield of a reaction is 48.05%.

7 0

3 years ago

Read 2 more answers

What is the pressure inside a 2.0 L bottle filled with 0.25 mol of carbon dioxide gas at 25 °C?

motikmotik

Answer:

3.1atm

Explanation:

Given parameters:

Volume of gas = 2L

Number of moles = 0.25mol

Temperature = 25°C = 25 + 273 = 298K

Unknown:

Pressure of the gas = ?

Solution:

To solve this problem, we use the ideal gas equation.

This is given as;

PV = nRT

P is the pressure

V is the volume

n is the number of moles

R is the gas constant = 0.082atmdm³mol⁻¹K⁻¹

T is the temperature

P = $\frac{nRT}{V}$

Now insert the parameters and solve;

P = $\frac{0.25 x 0.082 x 298}{2}$ = 3.1atm

8 0

3 years ago

Question 7-Which of the following is not an acid-base neutralization reaction?

docker41 [41]

Answer:- It is choice D. $H_2SO_4+2NaCl\rightarrow 2HCl+Na_2SO_4$

Explanations:- In general, a neutralization reaction is the reaction of an acid with base to form salt and water.

in first reaction the reaction is taking place between ammonia(a base) and hydrochloric acid(an acid) to form their salt(ammonium chloride). So, it is an acid-base neutralization reaction.

In second reaction, sodium hydroxide(a base) is reacting with acetic acid(an acid) to form their salt(sodium acetate) and water. So, it is an acid-base neutralization reaction.

In third reaction, Nitric acid is reacting with calcium hydroxide(a base) to form a salt(calcium nitrate) and water. So, it is an acid-base neutralization reaction.

In fourth reaction, sulfuruc acid is reacting a sodium chloride(a salt) to give a double replacement reaction. It is not an acid-base neutralization reaction as it's not taking place between an acid and base.

So, the correct choice is D. $H_2SO_4+2NaCl\rightarrow 2HCl+Na_2SO_4$

7 0

3 years ago

Read 2 more answers