Which of the following is correct?

A chemist measures the energy change ?H during the following reaction: 2HgO (s) ?2Hg (l) +O2 (g) =?H182.kJ Use the information t

Leni [432]

Answer:

The reaction is endothermic.

Yes, absorbed

3.06x10¹kJ are absorbed

Explanation:

In the reaction:

2HgO(s) → 2Hg(l) + O₂(g) ΔH = 182kJ

As ΔH >0,

<em>The reaction is endothermic</em>

<em />

As the reaction is endothermic, when the reaction occurs,

<em>the heat is absorbed.</em>

Now, based on the equation, when 2 moles of HgO (Molar mass: 216.59g/mol), 182kJ are absorbed.

72.8g are:

72.8g * (1mol / 216.59g) = 0.3361 moles HgO.

that absorb:

0.3361 moles HgO * (182kJ / 2 moles) =

<h3>3.06x10¹kJ are absorbed</h3>

8 0

3 years ago

WILL GIVE BRAINLEST! --

Paladinen [302]

Answer:

d

Explanation:

5 0

3 years ago

Read 2 more answers

A student titrates a 20.00 mL sample of an aqueous borax solution with 1.03 M H2SO4. If 2.07 mL of acid are needed to reach the

RSB [31]

Answer:

The concentration of the borax solution is 0.1066 M

Explanation:

Step 1: Dtaa given

Volume of a sample of aqueous borax solution = 20.00 mL = 0.020 L

Molarity of H2SO4 = 1.03 M

Volume of the H2SO4 = 2.07 mL = 0.00207 L

Step 2: The balanced equation

Na2B4O7*10H2O(borax) + H2SO4 ⇆ Na2SO4 + 4 H3BO3 + 5 H2O

Step 3: Calculate molarity of borax solution

b*Ca*Va = a * Cb*Vb

⇒with B = the coefficient of H2SO4 = 1

⇒with Ca = the concentration of borax = TO BE DETERMINED

⇒with Va = the volume of borax = 0.020 L

⇒with a = the coefficient of borax = 1

⇒with Cb = the concentration of H2SO4 = 1.03 M

⇒with Vb = the volume of H2SO4 = 0.00207 L

Ca*0.020 L = 1.03 M * 0.00207 L

Ca = (1.03 * 0.00207) / 0.020

Ca = 0.1066 M

The concentration of the borax solution is 0.1066 M

6 0

3 years ago

What determines the types of chemical reactions that an atom participates in? A. the number of electrons in the outermost electr

Dafna1 [17]

Answer:

The answer would be A. the number of electrons in the outermost electron shell.

Explanation:

These are called valence electrons which are transferred, shared, and rearranged by creating covalent bonds producing new substances.

Hope this helped! :)

8 0

2 years ago

GO FAST / WILL MARK BRAINLIEST / WILL GIVE THANKS / WILL GIVE 5 STARS

Nikitich [7]

<h2>question 1</h2>

Mg + 2HCl→ MgCl2 + H2

after balancing the coefficient for H2 is 1

<em><u>explanation </u></em>

since 1 is in front of H2 it is the coefficient for H2

question 2

the reaction is single replacement

<u><em>explanation</em></u>

because single replacement occurs when one element replaces another.
for the reaction of Mg + 2HCl→MgCl2 +H2 Chlorine

<h2> Question 3</h2>

The coefficient of H2 is 3

<em><u>explanation</u></em>

from the balanced chemical reaction
that is N2 +3H2 →2NH3 the coefficient in front of H2 is 3

<h2 /><h2> question 4</h2>

N2 + 3H2 → 2NH3 is a synthesis reaction

<u><em>explanation; </em></u>

Synthesis reaction occurs when two or more reactants combine to form a single product.

N2 reacted with H2 to form NH3 (ammonia) hence it is an example of synthesis reaction.

<h2>question 5</h2>

The sign that shows that a chemical reaction has occurred is color change, change in temperature and formation of a gas (bubble)

color change change in temperature, formation of precipitate and formation of a gas(bubble) is always an indicator of an occurrence of a chemical change.

<h2>Question 6</h2>

H2S is not a strong acid

<u><em>explanation</em></u>

strong acid undergo a complete electrolysis when dissociate in water for example HNO3
weak acid undergo a partial electrolysis when dissociate in water for example H2S

<h2>question 7</h2>

feels slippery is not a property of an acid

<u><em>explanation</em></u>

feel slippery is an example of a base
The properties of an acid are

sour taste
changes the color of an indicator
usually react with metal among others

<h2> Question 8</h2>

detergent with a PH of about 10 is a <u><em>basic</em></u>

<em><u>explanation</u></em>

Base has a Ph which range from 7.1 to 14
since the detergent has a PH of 10 is a basic

<h2>Question 9</h2>

The balanced chemical equation for the synthesis of NaBr is

2Na + Br2 →2 NaBr

<u><em>explanation</em></u>

This is because the equation obey the law of mas conversation

for example it has 2 atoms of Na in both reactant and product side

<h2>Question 10</h2>

reacts with metals is not a common property of a base

<u><em>Explanation</em></u>

base has

bitter taste,
feels slippery
turn red litmus paper blue among others

<h2> question 11</h2>

Hydrochloric acid have a PH in 0-6 range

<u><em>explanation</em></u>

HCl is a strong acid

acid has a PH which are below PH of 7 hence HCl has a PH which range from 0-6

<h2>Question 12</h2>

A brand shampoo which has a PH between 5 -6 is a weak acid

generally acid has a PH below 7
weak acid has a PH of between 5 -6 therefore brand shampoo is a weak acid

<h2>question 13</h2>

The PH that indicate a solution of a base is a PH of 12

<em><u>Explanation</u></em>

base has a PH which range between 7-14, hence a PH of 12 indicate that it is a Base

7 0

3 years ago