All categories

4 years ago

Which best describes thermal energy?

Chemistry

1 answer:

Sav [38]4 years ago

5 0

Answer:

It is the sum of internal energies of two or more substances

Explanation:

You might be interested in

Sodium hydroxide, NaoH , is a strong base that is used im industrial synthesis and processes such as making paper. What is the m

valentinak56 [21]

<h3>Answer:</h3>

1.926 g of NaOH

<h3>Explanation:</h3>

Concept tested: Mole and Avogadro's number

We need to know that , 1 mole of a compound contains number of molecules equivalent to the Avogadro's number.

Th Avogadro's number is 6.022 × 10^23

Therefore;

1 mole of a compound = 6.022 × 10^23 molecules

In this case; Our compound is NaOH

Therefore;

1 mole of NaOH contains 6.022 × 10^23 molecules

But; Molar mass of NaOH is 40.0 g/mol

Therefore;

40.0 g of NaOH contains 6.022 × 10^23 molecules

With this we can calculate the mass of 2.90 × 10^22 molecules

Mass of a compound = (number of molecules ÷ Avogadro's constant) × molar mass

Therefore;

Mass of NaOH =(2.90 × 10^22 molecules ÷ 6.022 × 10^23 molecules)40g

= 1.9263 g

= 1.926 g NaOH

Thus, the mass of NaOH is 1.926 g

8 0

4 years ago

Find the ph of a buffer that consists of 0.18 m ch3nh2 and 0.73 m ch3nh3cl (pkb of ch3nh2 = 3.35)?

ozzi

Hello!

First, we need to determine the pKa of the base. It can be found applying the following equation:

$pKa=14-pKb=14-3,35=10,65$

Now, we can apply the Henderson-Hasselbach's equation in the following way:

$pH=pKa+log( \frac{[CH_3NH_2]}{[CH_3NH_3Cl]} )=10,65+log( \frac{0,18M}{0,73M} )=10,04$

So, the pH of this buffer solution is 10,04

Have a nice day!

8 0

3 years ago

What is one way to test whether an unknown solution is acidic or basic

Dima020 [189]

A solution's pH will be a number between 0 and 14. A solution with a pH of 7 is classified as neutral. If the pH is lower than 7, the solution is acidic. When pH is higher than 7, the solution is basic. These numbers describe the concentration of hydrogen ions in the solution and increase on a negative logarithmic scale. For example, If Solution A has a pH of 3 and Solution B has a pH of 1, then Solution B has 100 times as many hydrogen ions than A and is therefore 100 times more acidic.

4 0

3 years ago

Calculate the volume of 0.100 m hcl required to neutralize 1.00 g of ba(oh)2 (molar mass = 171.3 g/mol).

dedylja [7]

The balanced chemical equation between HCl and $Ba(OH)_{2}$ is:

$2HCl (aq) + Ba(OH)_{2}(aq) -->BaCl_{2}(aq) + 2 H_{2}O(l)$

Moles of $Ba(OH)_{2}$ = $1.00 g Ba(OH)_{2} * \frac{1 mol Ba(OH)_{2}}{171.3 g Ba(OH)_{2}} = 0.00584 mol Ba(OH)_{2}$

Moles of HCl required to neutralize $Ba(OH)_{2}$ :

$0.00584 mol Ba(OH)_{2} * \frac{ 2 mol HCl}{1 mol Ba(OH)_{2}} = 0.01168 mol HCl$

Calculating the volume of HCl from moles and molarity:

$0.01168 mol HCl * \frac{1 L}{0.100 mol} * \frac{1000 mL}{1 L} = 116.8 mL$

7 0

3 years ago

Read 2 more answers

A radioactive element having and atomic number 82 and atomic mass 214 emits a beta particle. The resulting element is:______.

aalyn [17]

Answer:

$\frac{214}{83} Bi$

Explanation:

In beta emission, a neutron is converted into a proton thereby reducing the neutron:proton (N/P) ratio.

When a beta emission occurs, the mass number remains the same while the nuclear charge increases by one unit. The daughter nucleus is found one place to the right of its parent in the periodic table.

5 0

3 years ago