Can someone help? Please show work for each one!

Answer:

Element   atom    molar mass     Total        % composition

Na               1            23                    40             57.5 %

O                 1            16                     40              40%

H                1               1                      40              2.5 %

The given compound is NaOH.

Na : number of atom= 1

Molar mass= 23 g/mol

Total mass of NaOH = 40 g/mol

% composition by mass = [tex]\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{23}{40}\times 100=57.5\%[/tex]

O : number of atom= 1

Molar mass= 16 g/mol

Total mass of NaOH = 40 g/mol

% composition by mass = [tex]\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{16}{40}\times 100=40\%[/tex]

H : number of atom= 1

Molar mass= 1 g/mol

Total mass of NaOH = 40 g/mol

% composition by mass = [tex]\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{1}{40}\times 100=2.5\%[/tex]

Answer:

Pure substances are substances that are made up of only one kind of particles and has a fixed or constant structure. Pure substances are further classified as elements and compounds. An element is a substance that consists of only one type or kind of atom

Answer:

define the term pure substance​ :

A pure substance does not have to be of a single element or compound, This can either be one single element or one single compound, but every sample of this substance that you examine must contain exactly the same thing with a fixed, definite set of properties

Explanation:

Answer:

both spheres have a positive charge

Answer:

I would say 17.25.

Explanation:

Answer:

The formation of a gas is a clue to chemical changes. The bubbles of gas that you observed form when an antacid is dropped into water is an example of change. ... As wood burns, it turns into a pile of ashes and gases that rise into air.

Explanation:

Answer:

All of them derive from a common ancestor. They each share something in their DNA that ties into their past selves, which were more closely related. As they evolved, they became more and more distant, but we can still trace them back to the olden days.

Also they all have scales.

Hope this was at least semi-useful.

Answer:

yes

Explanation:

solubility rules allow prediction of what products will be insoluble in water.

Answer:

company smokes

wastes (liquid and solid)

Answer:

Mass of 1 mole of Aluminium = Mass of 6.02 x 10 23atoms of Aluminium =  26.98 grams.

Explanation:

1 mole of any element or molecule has 6.02 x 10 23atoms or subparts.

Hence 1 mole of aluminum will also have 6.02 x 10 23atoms. Hence, it is clear that mass of 1 mole of Aluminium will be equal to 6.02 x 10 23atoms of Aluminium.

Thus,

Mass of 1 mole of Aluminium = Mass of 6.02 x 10 23atoms of Aluminium =  26.98 grams.

Explanation:

these are the formula that u need to know

1. moles= concentrate × volume

2. moles = mass / mr

3. moles = volume in dm3 / 24dm^3

4. moles = Pressure in pa × Volume in m3 / 8.031 × temperature in K

hope this helps :)

Answer:

High blood pressure. High blood pressure (hypertension) is one of the most important risk factors for CVD.

High cholesterol - High-fat diet.

Answer:

Special type of surface that repels liquid

Explanation:

Answer:

The large relative distances between particles in a gas means that there is considerable empty space between the particles.

The assumption that particles in a gas are relatively far apart explains gas compressibility.

Compressibility is a measure of how much the volume of matter decreases under pressure.

Energy is released by a gas when it is compressed

Explanation:

The kinetic molecular theory establishes that gases are composed of molecules. These molecules of gas are far apart from each other hence there is a considerable empty space between the gas molecules. As a result of these empty spaces between gas molecules, it is possible to compress a gas.

Compressibility is defined as a measure of how much the volume of matter decreases under pressure. When a gas is compressed, work is done on the gas and energy is evolved hence the gas heats up.

Answer:

c: low melting point

Explanation:

melting point is dependent on intermolecular forces. in covalent compounds, electrons are shared more equally. this means there is less separation of positive and negative charges within the molecules.

Answer: The complete nuclear symbol will be [tex]_8^{18}\textrm {O}[/tex]

Explanation:

The nuclear symbol is written as: [tex]_Z^A\textrm {X}[/tex] where Z= atomic number , A = mass number X = symbol of element

Atomic number is defined as the number of protons or number of electrons that are present in an atom.

For an electrically neutral atom,

Atomic number = Number of electrons = Number of protons = 8

Mass number is defined as the sum of number of protons and neutrons that are present in an atom.

Mass number = Number of protons + Number of neutrons  

Mass number = 8 + 10 = 18

Thus complete symbol will be [tex]_8^{18}\textrm {O}[/tex]

Answer:

pluto is considered a dwarf planet because it did not meet the three criteria the IAU uses to define a full sized planet

Explanation:

Answer:

60

Explanation:

Answer:

its actually 83° rounding it so choose that

Answer:

B) go look on the periodic table for the atomic number

Explanation:

The atomic number is how many protons is in an atom

Answer:

Either A or B

Explanation: Because I learned it on Edge. :)

Answer:

Copper(II) sulphate – sodium hydroxide reaction

The reaction between copper(Il) sulphate and sodium hydroxide solutions is a good place to start. If you slowly add one to the other while stirring, you will get a precipitate of copper(II) hydroxide, Cu(OH)2.

Answer:

320 grams of sulfur trioxide are required to produce 4.00 mol of sulfuric acid.

Explanation:

The balanced reaction is:

SO₃ + H₂O → H₂SO₄

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:

Being the molar mass of each compound:

By reaction stoichiometry, the following mass quantities of each compound participate in the reaction:

Then you can apply the following rule of three: if 1 mole of sulfuric acid is produced by the reaction of 80 grams of sulfur trioxide, 4 moles of sulfuric acid is produced from how much mass of sulfur trioxide?

[tex]mass of sulfur trioxide= \frac{4 moles of sulfuric acid* 80 grams of sulfur trioxide}{1 mole of sulfuric acid }[/tex]

mass of sulfur trioxide= 320 grams

320 grams of sulfur trioxide are required to produce 4.00 mol of sulfuric acid.

The mass of the required compound is 320 grams

Given the chemical equation expressed as:

[tex]SO_3 + H_2O \rightarrow H_2SO_4[/tex]

According to stochiometry, 1 mole of SO3  produces 1 mole of H2SO4, hence the moles of SO3 will also be 4.00moles

Determine the mass of SO3

Mass = mole * molar mass

Mass = 4.0 * [32+3(16)]

Mass = 4.0 * 80

Mass = 320 grams

The mass of the required compound is 320 grams

Learn more on stoichiometry here:  https://brainly.com/question/16060223

Answer:

i fond nothing sooory

pic so PC

Explanation:

Competition stems from the fact that resources are limited. There are simply not enough of some resources for all individuals to have equal access and supply. Competition can occur between organisms of the same species, or between members of different species.

Answer:

Lithosphere: Volcanos..

Hydrosphere: Rain falls..

biosphere: Plants..

Explanation:

Answer:

As you noticed, the percent-error formula needs you to use a value in the ... The actual absolute zero is 275C below my coldest recorded value. ... The only way your calculations makes sense is you're trying to calculate how ... Next, I'll interpret "I found that AZ is at -258°C" as "I calculated AZ to be 260 degrees below 2°C".

Explanation:

The experimental error will be 8.95%

The formula  used for calculating the percentage error is expressed as:

[tex]\% error=\frac{|exp. \ value - actual \ value|}{actual \ value} \times 100[/tex]

Given the following parameters

Actual value = −273.15 degrees Celcius

Let the experimental value be 300 degrees Celcius (since we are not given)

[tex]\% error=\frac{|300 - 273.15|}{300} \times 100\\\% error=\frac{|26.85|}{300} \times 100\\\% error=8.95\%[/tex]

Hence the experimental error will be 8.95%

Learn more on experimental error here; https://brainly.com/question/2764830

Answer:

brainly blurred the half of the question i cant read it completely

Explanation: