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2 years ago

+++TO BE ANSWERED ASAP (WILL PUT BRAINLIEST!!!)+++

Chemistry

1 answer:

goldfiish [28.3K]2 years ago

5 0

Answer:

Phenolphthalein is an acid indicator, which means when we add water (pH 7) to it, it ionizes giving a pink color. We all know acid gives in solution. When we add phenolphthalein to acid due to the common ion effect concentration increases. turned the solution pink.

Explanation:

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What is the mass of 0.5 g/cm3

nevsk [136]

Answer:

$1cm3 \: is \: the \: answer.$

3 0

3 years ago

When hydrogen sulfide gas is bubbled into a solution of sodium hydroxide, the reaction forms sodium sulfide and water. How many

My name is Ann [436]

Answer:

0.0803g of Na2S are produced

Explanation:

Hydrogen sulfide, H2S, reacts with sodium hydroxide, NaOH, to produce sodium sulfide, Na2S and water.

2NaOH + H2S → 2H2O + Na2S

To solve this question we must find the moles of each reactant. With the chemical quation we can find the limiting reactant. With limiting reactant we can find the moles of Na2S and its mass

<em>Moles NaOH -Molar mass: 40g/mol-</em>

0.0823g * (1mol / 40g) = 0.002058moles

<em>Moles H2S -Molar mass: 34.082g/mol-</em>

2.68g * (1mol / 34.082g) = 0.0786 moles

For a complete reaction of 0.0786 moles of H2S are needed:

0.0786 moles H2S * (2mol NaOH / 1mol H2S) = 0.157 moles NaOH

As there are just 0.002058 moles, <em>NaOH is limiting reactant.</em>

The moles of Na2S produced are:

0.002058moles NaOH * (1mol Na2S / 2mol NaOH) = 0.001029 moles Na2S

<em>Mass Na2S -Molar mass: 78.0452g/mol-</em>

0.001029 moles Na2S * (78.0452g / mol) =

<h3>0.0803g of Na2S are produced</h3>

8 0

3 years ago

•In carrying out an experiment based on this reaction, 2.45 L of dinitrogen tetroxide were used. How many liters of nitrogen dio

lapo4ka [179]

Dinitrogen tetroxide decomposes to give nitrogen dioxide according to equation below
N2O4--->2NO2
According to avogadros law
1 moles =22.4 l
what about 2.45 l
=2.45l x1 mole/22.4=0.1094 moles
by use of reacting ratio that 1 :2
the moles of No2 = 0.1094 x2=0.2188 moles

1 moles= 22.4 l
what about 0.2188moles
=(0.2188moles x22.4 l) /1moles=4.90 L

3 0

4 years ago

A solid ice cube absorbs 151.7 J of energy as it warms from 0.00°C to 4.70°C. What is the mass of the ice cube?

chubhunter [2.5K]

I believe you do 151.7= 4.18x (4.70) because you use the formula q=mcat

5 0

4 years ago

. Dimethyl nitrosamine is a known carcinogen. It can be formed in the intestinal tract when digestive juices react with the nitr

8090 [49]

Answer: The empirical formula for the given compound is $C_2H_6ON_2$

Explanation:

The chemical equation for the combustion of hydrocarbon having carbon, hydrogen and oxygen follows:

$C_xH_yN_z+O_2\rightarrow CO_2+H_2O$

where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and nitrogen respectively.

We are given:

Mass of $CO_2=5.134g$

Mass of $H_2O=3.173g$

We know that:

Molar mass of carbon dioxide = 44 g/mol

Molar mass of water = 18 g/mol

For calculating the mass of carbon:

In 44 g of carbon dioxide, 12 g of carbon is contained.

So, in 5.134 g of carbon dioxide, $\frac{12}{44}\times 5.134=1.4g$ of carbon will be contained.

For calculating the mass of hydrogen:

In 18 g of water, 2 g of hydrogen is contained.

So, in 3.173 g of water, $\frac{2}{18}\times 3.173=0.35g$ of hydrogen will be contained.

For calculating the mass of nitrogen:

As, 100 g of sample contains 37.87 % of nitrogen

So, 4.319 g of sample contains $\frac{37.87}{100}\times 4.319=1.635g$ of nitrogen

For calculating the mass of oxygen:

Mass of oxygen in the compound = (4.319) - (1.4 + 0.35 + 1.635) = 0.934 g

To formulate the empirical formula, we need to follow some steps:

Step 1: Converting the given masses into moles.

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{1.4g}{12g/mole}=0.116moles$

Moles of Hydrogen = $\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{0.35g}{1g/mole}=0.35moles$

Moles of Oxygen = $\frac{\text{Given mass of oxygen}}{\text{Molar mass of oxygen}}=\frac{0.934g}{16g/mole}=0.058moles$

Moles of Nitrogen = $\frac{\text{Given mass of nitrogen}}{\text{Molar mass of nitrogen}}=\frac{1.635g}{14g/mole}=0.116moles$

Step 2: Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 0.058 moles.

For Carbon = $\frac{0.116}{0.058}=2$

For Hydrogen = $\frac{0.35}{0.058}=6.03\approx 6$

For Oxygen = $\frac{0.058}{0.058}=1$

For Oxygen = $\frac{0.116}{0.058}=2$

Step 3: Taking the mole ratio as their subscripts.

The ratio of C : H : O : N = 2 : 6 : 1 :2

Hence, the empirical formula for the given compound is $C_2H_6O_1N_2=C_2H_6ON_2$

8 0

4 years ago