All categories

3 years ago

Which of the following about a balanced chemical reactions is

Chemistry

1 answer:

gavmur [86]3 years ago

6 0

Answer:

A balanced chemical equation must always include coefficients on every reactant and product.

Explanation:

<u>A balanced chemical equation does not need to include coefficients on every reactant and product.</u>

For example, below is a balanced chemical equation in which the reactants and the products have no coefficients whatsoever:

NaOH(aq) + HCl (aq) -----> NaCl (s) + H2O (l)

<em>Of course, a properly written chemical equation must include the states of matter of all the substances in the reaction and the number of atoms of each element must balance both in the reactant and product sides of the equation. Generally, a balanced chemical equation must obey the law of conservation of matter which opines that matter can neither be created nor destroyed but can only be converted from one form to another. </em>

Hence, that a balanced chemical equation must always include coefficients on every reactant and product is not true.

You might be interested in

Select all of the following that are recessive alleles.

const2013 [10]

All of the lower case letters are recessive

8 0

2 years ago

A system gains 652 kJ of heat, resulting in a change in internal energy of the system equal to +241 kJ. How much work is done?

levacccp [35]

Answer:

-411 kj

Explanation:

We solve by using this formula

∆U = ∆Q + ∆W

This formula is the first law of thermodynamics

Change in internal energy U = +241

Heat gained by system Q = 652

Putting the value into the equation

+241 = 652 + W

Workdone = 241 - 652

Workdone = -411 kj

Since work done is negative it means that work was done by the system

3 0

2 years ago

Identify the oxidizing agent and the reducing agent for 4Li(s) + O_2 (g) to 2Li_2O(s).

wolverine [178]

Answer: Li is the reducing agentg and O is the oxidizing agent.

Explanation:

1) The oxidizing agent is the one that is reduced and the reducing agent is the one that is oxidized.

2) The given reaction is:

4Li(s) + O₂ (g) → 2 Li₂O(s)

3) Determine the oxidation states of each atom:

Li(s): oxidation state = 0 (since it is alone)

O₂ (g): oxidation state = 0 (since it is alone)

Li in Li₂O (s) +1

O in Li₂O -2

That because 2× (+1) - 2 = 0.

4) Determine the changes:

Li went from 0 to + 1, therefore it got oxidized and it is the reducing agent.

O went from 0 to - 2, therefore it got reduced and it is the oxidizing agent.

7 0

3 years ago

Read 2 more answers

Calculate the ph of a solution in which [oh–] = 4.5 × 10–9m.

frosja888 [35]

pOH = -LOG([OH])

pOH = -LOG(4.5*10^-9)

pOH = 8.34

pH + pOH = 14

pH = 14 - 8.34 = 5.65

hope this helps!

5 0

3 years ago

A student weighs an empty flask and stopper and finds the mass to be 53.256 g. She then adds about 5 mL of an unknown liquid and

Delvig [45]

Answer:

a. The pressure in the flask open to the atmosphere during the vaporization of the unknown liquid is equal to the prevailing atmospheric pressure equivalent to 0.957734 atm

Explanation:

The mass of the empty flask and stopper, m = 53.256 g

The volume of the unknown liquid she adds = 5 mL

The temperature of the water in which she heats up the flask = 98.8 °C = 371.95 K

The mass of the flask and the condensed vapor = 53.780 g

The volume of the flask, V = 231.1 mL

The atmospheric pressure, P = 728 mm Hg

a. We note that the student stoppers the flask after all the liquid has evaporated. Therefore, given that the flask was open to the atmospheric pressure as the liquid evaporates, the pressure of the vapor in the flask is equal to the prevailing atmospheric pressure, or 728 mmHg

Using a calculator, 728 mm Hg is equivalent to 0.957734 atm.

3 0

3 years ago