Which solution when mixed with a drop of bromthymol blue will cause the indicator to change from blue to yellow

What are three similarities between biotic and abiotic factors?

Viktor [21]

1. Both part of the ecosystem
2. There are biotic objects on abiotic objects ( caterpillars on trees ) and abiotic objects on biotic things ( pollen on bees )
3. Both are made of atoms

6 0

3 years ago

I need this answer. any thing will help

Licemer1 [7]

Answer: condensaytion

Explanation: its reverse vaporation instead of water turning into gas gas turns into water

8 0

3 years ago

A compound is 7.74% hydrogen and 92.26% carbon by mass. At 100°C a 0.6883 g sample of the gas occupies 250 mL when the pressure

ycow [4]

<u>Answer:</u> The molecular formula for the compound is $C_6H_6$

<u>Explanation:</u>

We are given:

Percentage of C = 92.26 %

Percentage of H = 7.74 %

Let the mass of compound be 100 g. So, percentages given are taken as mass.

Mass of C = 92.26 g

Mass of H = 7.74 g

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

<u>Step 1:</u> Converting the given masses into moles.

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{92.26g}{12g/mole}=7.68moles$

Moles of Hydrogen = $\frac{\text{Given mass of Hydrogen}}{\text{Molar mass of Hydrogen}}=\frac{7.74g}{1g/mole}=7.74moles$

<u>Step 2:</u> 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 7.68 moles.

For Carbon = $\frac{7.68}{7.68}=1$

For Hydrogen = $\frac{7.74}{7.68}=1$

<u>Step 3:</u> Taking the mole ratio as their subscripts.

The ratio of C : H = 1 : 1

The empirical formula for the given compound is $CH$

<u>Calculating the molar mass of the compound:</u>

To calculate the molecular mass, we use the equation given by ideal gas equation:

PV = nRT

Or,

$PV=\frac{m}{M}RT$

where,

P = pressure of the gas = 820 torr

V = Volume of gas = 250 mL = 0.250 L (Conversion factor: 1 L = 1000 mL )

m = mass of gas = 0.6883 g

M = Molar mass of gas = ?

R = Gas constant = $62.3637\text{ L. torr }mol^{-1}K^{-1}$

T = temperature of the gas = $100^oC=(100+273)K=373K$

Putting values in above equation, we get:

$820torr\times 0.250L=\frac{0.6883g}{M}\times 62.3637\text{ L torr }mol^{-1}K^{-1}\times 373K\\\\M=\frac{0.6883\times 62.3637\times 373}{820\times 0.250}=78.10g/mol$

For determining the molecular formula, we need to determine the valency which is multiplied by each element to get the molecular formula.

The equation used to calculate the valency is:

$n=\frac{\text{Molecular mass}}{\text{Empirical mass}}$

We are given:

Mass of molecular formula = 78.10 g/mol

Mass of empirical formula = 13 g/mol

Putting values in above equation, we get:

$n=\frac{78.10g/mol}{13g/mol}=6$

Multiplying this valency by the subscript of every element of empirical formula, we get:

$C_{(1\times 6)}H_{(1\times 6)}=C_6H_6$

Hence, the molecular formula for the compound is $C_6H_6$

8 0

3 years ago

An element has 2 neutrons, 2 electrons and 2 protons. Which element does this describe? Is it a neutral atom, isotope, or an ion

Y_Kistochka [10]

Considering the definition of neutral atom, mass number and net charge, the element is a neutral atom, with a net charge equal to zero and a mass number of 4.

<h3>Neutral atom and ion</h3>

All atoms are made up of subatomic particles: protons and neutrons, which are part of their nucleus, and electrons, which revolve around them. Protons are positively charged, neutrons are neutrally charged, and electrons are negatively charged.

A neutral atom is one that has no electrical charge because it has the same number of protons and electrons.

In contrast, ions are atoms or groups of atoms that have an electrical charge and are formed by the gain or loss of electrons from the atom.

<h3>Mass number</h3>

The mass number tells us the total number of particles in the nucleus. That is, the mass number is the sum of the number of protons and the number of neutrons in the atomic nucleus:

Mass number = (number of protons) + (number of neutrons)

It is represented by the letter A.

<h3>Net charge</h3>

The net charge corresponds to the algebraic sum of all the charges that a atom possesses.

In this case, an element has:

2 neutrons.
2 electrons.
2 protons.

Then, the net charge is calculated as:

net charge= 2× 0 [charge of neutron] + 2× (+1) [charge of proton] + 2× (-1) [charge of electron]

<u><em>net charge= 0</em></u>

This element has no electrical charge, or net charge is zero. Then, the element is a neutral atom.

On the other hand, the mass number is the sum of the number of protons and the number of neutrons. So, in this case:

mass number= 2 protons + 2 neutrons

<u><em>mass number= 4</em></u>

Finally, the element is a neutral atom, with a net charge equal to zero and a mass number of 4.

Learn more about

neutral atom:

brainly.com/question/24652228

brainly.com/question/18242008

brainly.com/question/18330612

mass number:

brainly.com/question/1758023

brainly.com/question/5527493

net charge:

brainly.com/question/24752359

#SPJ1

4 0

1 year ago

What other traits besides phisical ones could be passed on from parent offspring

OlgaM077 [116]

Answer:

Love for Music

Explanation:

This is one example of many non-physical traits. In the womb a mother can listen to her favorite music and the growing baby could grow to like it in the womb!

This is just one of the many other traits that could be passed to their offspring.

Hope this Helps!

3 0

2 years ago