Which statement is true for a solution when its concentration of hydroxide ions increases?

Describe what occurs when a gas is collected by water displacement, including why a table of water vapor pressure values is need

Radda [10]

When a gas bubbles through water, small droplets of water are usually picked up along for the ride and are mixed in with the gas above the water inside the eudiometer tube. The water vapor takes up room, but isn't the important gas that you need to measure. The table of water vapor is needed to subtract the unwanted water vapor from the collection of gases.

5 0

2 years ago

How many moles in 2.21 x10E24 atoms of aluminum

lisov135 [29]

<h3>Answer:</h3>

3.67 mol Al

<h3>General Formulas and Concepts:</h3>

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right<u> </u>

<u>Chemistry</u>

<u>Atomic Structure</u>

Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

<u>Stoichiometry</u>

Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

2.21 × 10²⁴ atoms Al

<u>Step 2: Identify Conversions</u>

Avogadro's Number

<u>Step 3: Convert</u>

Set up: $\displaystyle 2.21 \cdot 10^{24} \ atoms \ Al(\frac{1 \ mol \ Al}{6.022 \cdot 10^{23} \ atoms \ Al})$
Divide: $\displaystyle 3.66988 \ mol \ Al$

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 3 sig figs.</em>

3.66988 mol Al ≈ 3.67 mol Al

7 0

2 years ago

1) How much energy would be required to melt 15.0 g of ice at 0°C?

DerKrebs [107]

Answer:

5010J

Explanation:

The following data were obtained from the question:

Mass (m) = 15g

Heat of fusion (ΔHf) = 334J/g

Heat required (Q) =..?

The heat energy required to melt the ice can be obtained as follow:

Q = m·ΔHf

Q = 15 x 334

Q = 5010J

Therefore, the heat energy required to melt the ice is 5010J.

8 0

2 years ago

The enthalpy of solution (∆H) of KOH is -57.6 kJ/mol. If 3.66 g KOH is dissolved in enough water to make a 150.0 mL solution, wh

Wewaii [24]

When 3.66 g of KOH (∆Hsol = -57.6 kJ/mol) is dissolved in 150.0 mL of solution, it causes a temperature change of 5.87 °C.

The enthalpy of solution of KOH is -57.6 kJ/mol. We can calculate the heat released by the solution (Qr) of 3.66 g of KOH considering that the molar mass of KOH is 56.11 g/mol.

$3.66g \times \frac{1mol}{56.11g} \times \frac{(-57.6kJ)}{mol} = -3.76 kJ$

According to the law of conservation of energy, the sum of the heat released by the solution of KOH (Qr) and the heat absorbed by the solution (Qa) is zero.

$Qr+Qa = 0\\\\Qa = -Qr = 3.76 kJ$

150.0 mL of solution with a density of 1.02 g/mL were prepared. The mass (m) of the solution is:

$150.0 mL \times \frac{1.02g}{mL} = 153 g$

Given the specific heat capacity of the solution (c) is 4.184 J/g･°C, we can calculate the change in the temperature (ΔT) of the solution using the following expression.

$Qa = c \times m \times \Delta T\\\\\Delta T = \frac{Qa}{c \times m} = \frac{3.76 \times 10^{3}J }{\frac{4.184J}{g.\° C } \times 153g} = 5.87 \° C$

When 3.66 g of KOH (∆Hsol = -57.6 kJ/mol) is dissolved in 150.0 mL of solution, it causes a temperature change of 5.87 °C.

Learn more: brainly.com/question/4400908

7 0

2 years ago

If exactly 59.6 g of nitrogen gas is needed to inflate your air bag to the

Inga [223]

Answer:

We need 92.3 grams of sodium azide

Explanation:

Step 1: Data given

Mass of nitrogen gas = 59.6 grams

Molar mass of nitrogen gas = 28.0 g/mol

Molar mass of sodium azide = 65.0 g/mol

Step 2: The balanced equation

2NaN3 → 2Na + 3N2

Step 3: Calculate moles nitrogen gas

Moles N2 = mass N2 / molar mass N2

Moles N2 = 59.6 grams/ 28.0 g/mol

Moles N2 = 2.13 moles

Step 4: Calculate moles NaN3

for 2 moles NaN3 we'll have 2 moles Na and 3 moles N2

For 2.13 moles N2 we need 2/3* 2.13 = 1.42 moles NaN3

Step 5: Calculate mass NaN3

Mass NaN3 = Moles NaN3 * molar mass NaN3

Mass NaN3 = 1.42 moles * 65.0 g/mol

Mass NaN3 = 92.3 grams

We need 92.3 grams of sodium azide

7 0

2 years ago