Answer:
[tex]\boxed {\boxed {\sf A. \ 2.48 \ mol \ Na_2O}}[/tex]
Explanation:
We are asked to convert an amount in grams to moles. To do this, we use the molar mass. This is the number of grams in one mole of a substance. It is the same value numerically as the atomic mass on the Periodic Table, however the units are grams per mole, not atomic mass units.
Look up the molar masses for the individual elements.
Sodium (Na): 22.9897693 g/mol Oxygen (O): 15.999 g/molLook back at the formula: Na₂O. Notice there is a subscript of 2 after sodium. This means there are 2 atoms of sodium in every molecule, so we have to multiply sodium's molar mass by 2 before adding oxygen's.
Na₂O: 2(22.9897693 g/mol)+ 15.999 g/mol = 61.9785386 g/molSet up a ratio using the molar mass.
[tex]\frac {61.9785386 \ g \ Na_2O}{1 \ mol \ Na_2O}[/tex]
Multiply by the given number of grams.
[tex]154 \ g \ Na_2O*\frac {61.9785386 \ g \ Na_2O}{1 \ mol \ Na_2O}[/tex]
Flip the ratio so the grams of sodium oxide can cancel each other out.
[tex]154 \ g \ Na_2O*\frac {1 \ mol \ Na_2O}{61.9785386 \ g \ Na_2O}[/tex]
[tex]154 *\frac {1 \ mol \ Na_2O}{61.9785386 }[/tex]
[tex]\frac {154}{61.9785386 } \ mol \ Na_2O[/tex]
[tex]2.48473106141 \ mol \ Na_2O[/tex]
The original measurement of grams given has 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredth place.
2.48473106141The 4 in the thousandth place tells us to leave the 8.
[tex]2.48 \ mol \ Na_2O[/tex]
There are 2.48 moles of sodium oxide in 154 grams, so choice A is correct.
The limestone used in building the Egyptian pyramids was used because it is _____________
O soft and sticky
O easily melted
O hard and brittle
Answer:
hard and brittle
hope this helps you ☺️☺️
good night take care sweet dream
Dissolving salt in water causes a CHEMICAL change. true or false
Answer:
False. It is a PHYSICAL change.
Question 6
Simplify the following expression
-3 + 4(a - 3b + 2) - 514 - a + 3b)
What is the phase label on HCl?
A. g
B. aq
C.
D. e
E. s
Answer:
B. aq if the reaction is inorganic (double or single displacement), neutralization, etc.
Explanation:
Hello there!
In this case, unfortunately we are not given the undergoing chemical reaction; however, in the most of the double displacement, neutralization, precipitation and in general, inorganic reactions, the hydrochloric acid must be B. aq as it must be dissolved in water as the reaction media. On the other hand, in some organic reactions, it can be either aqueous or gaseous, the latter, specially as a product. For that reason, you will need to make sure whether your reaction is organic or inorganic to correctly figure out the phase label.
Best regards!
Calculate the pOH of this solution. pH = 1.90 pOH =
Answer:
12.1Explanation:
Since the pH has been given, the pOH can be found by using the formula
pH + pOH = 14
pOH = 14 - pH
From the question we have
pOH = 14 - 1.9
We have the final answer as
12.1Hope this helps you
Answer:
12.10
Explanation:
Which of the following is NOT one of the three layers that terrestrial worlds have?
Core
Crust
Mantle
Seismic zone
I take in oxgyen from the air and send it into your bloodstream. I also remove the carbon dioxide from your body. What system am I?
muscular system
respiratory system
digestive system
skeletal system please help
Given the following skeleton equation, what are the coefficients for the chemicals in the reaction? __ FeSO4 + __ Al(OH)3 → __ Al2(SO4)3 + __ Fe(OH)2
Answer:
3 FeSO4 + 2 Al(OH)3 -> 1 Al2(SO4)3 + 3 Fe(OH)2
Explanation:
What is the name of the planet next to the label A?
Solar System
EARTH
SUN
A. Uranus
O ОО
B. Neptune
C. Jupiter
d
D. Saturn
Please help
Answer:
B. Neptune. Neptune is next to Uranus
If 0.1 M solution of CH3COOH of acetic acid will beis 0.01 % ionized in aqueous solution,the ionization constant
a. 10^-7 .
b. 10^-5 .
c. 10^-3 .
d. 10^-9
Answer:
its answer b
Explanation:
What is the name of the compound Cd(MnO4)2?
A
cadmium manganate
B.
cadmium manganite
C.
cadmium permanganate
O
D.
admium permanganite
In this project, you will develop a model of a chemical reaction that either releases energy or absorbs energy. Whether a reaction releases or absorbs energy depends on the overall difference in the bond energies of the reactants and products. Your model should show the relationships between the parts of the system. These parts are the molecules and atoms that take part in the reaction. The model should also distinguish the reaction system from other systems.
Answer:
that ain't chemistry that's science
A mixture of water and water vapor is present in a closed vessel at 20 degrees Celsius. the total pressure of the system is 755.0 mmHg. Partial pressure of water vapor at 20 degrees Celsius equals 17.5 mm Hg. What is the partial pressure of H2
Answer:
737.5 mmHg
Explanation:
Ptotal=PH2O+PH2
P is the pressure and since we have Ptotal and PH2O, we can solve for PH2
755=17.5+x
755-17.5=x
x=737.5
1. There are basic particles from which matter could
be made except
salt.
B
atom.
Cion.
D molecules.
Answer: Hello, There! your Answer is Below
Option A Salt
Explanation:
Salt is A Chemical Used For Varites of Purposes, So It's not Part of Matter.
Atom being the Smallest Part of Molecule And ion Are Charge Which is Part of Matter.
Hope this helps!!
Have a great day!!!
atoms that have a high electronegativity...
Helium, bromine, agron, neon,flourine
Match each definition to the appropriate term.
Sum of the internal energy plus the product of the pressure and volume for a reaction
The extent of randomness in a system
The condition that a reaction takes place without outside help
Difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature
Solution in which no more solute can be dissolved in the solvent
Answer:
Enthalpy, Entropy, Spontaneity, Gibbs free energy, saturated solution
Explanation:
Enthalpy is defined as the heat released or the heat absorbed during the process at a constant pressure which is equal to the Enthalpy shift. Enthalpy is also called as heat content and it is the sum total of internal energy and the product of the volume and pressure of a system.
Entropy is defined as the measure of randomness of a system or the disorder of the system.
Spontaneity is defined as the condition of being spontaneous. It is the condition where a reaction takes place without any help from outside.
Gibbs free energy is defined as the energy that is used to quantify the maximum work done in a thermodynamic system at constant temperature and pressure. It is the also known as the Gibbs energy or function.
Saturated solution is defined as the solution where the maximum amount of the dissolved solute is present in the solvent. In case of a saturated solution, the extra solute does not dissolve. In order words, it is a solution where no more solute can dissolved in solvent.
The sum of the internal energy plus the product of the pressure and volume for a reaction represents Enthalpy , Entropy is the extent of randomness in a system, Spontaneity is that condition that a reaction takes place without outside help, Gibb's free energy is the difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature and Saturated solution in which no more solute can be dissolved in the solvent.
Which properties will define chemical reaction?Thermodynamically chemical reactions will be define by considering the properties like entropy, enthalpy, free energy, internal energy, temperature and many more.
Enthalpy of the reaction tells about the total amount of heat released or absorbed during a chemical reaction, and it is calculated as sum of the internal energy plus the product of the pressure and volume for a reaction.Entropy of any reaction tells about the randomness and uncertainty present within the molecule or atoms.Spontaneity of any chemical reaction tells about the ease of completion of that reaction. Gibb's free energy is the total energy involved in that reaction and represented as difference of the enthalpy (of a system) minus the product of the entropy and absolute temperature.Saturated solutions are those solutions in which all solute get completely dissolved, no solute will remain undissolved.Hence correct answers are Enthalpy , Entropy ,Spontaneity, Gibb's free energy and Saturated solutions.
To know more about saturated solutions, visit the below link:
https://brainly.com/question/4529762
What value is equivalent to 7.2 kilograms
Answer: 15.8732828773 pounds
Explanation:
Write a scientific explanation that answers the following question: Is matter conserved during a
chemical reaction in both closed and open systems?
Claim:
Evidence:
Reasoning:
Answer:
Matter is conserved during all chemical reactions because matter cannot be created or destroyed.
Explanation:
Which of the following is a primary source for scientific information? O A. Doctoral theses OB. A handbook of scientific facts O C. Reviews of scientific studies D. Public opinion about a scientific issue
A tree can be a _________________________ for insects in a schoolyard.
Answer:
habitat/shelter
Explanation:
Convert 2.178×1010 g to each of the following units.
Answer:
2.178x10⁷kg, 2.178x10¹³mg, 2.178x10¹⁶μg, 2.178x10⁴ metric tons.
Explanation:
The units are kg, μg, mg and metric tons (1metric ton = 1000kg)
To solve this question we must convert, first, the grams to milligrams, and to kilograms. Then, the kilograms to metric tons and the milligrams to micrograms:
kg:
2.178x10¹⁰g * (1kg / 1000g) = 2.178x10⁷kg
mg:
2.178x10¹⁰g * (1000mg / 1g) = 2.178x10¹³mg
μg:
2.178x10¹³mg * (1000μg / 1mg) = 2.178x10¹⁶μg
metric tons:
2.178x10⁷kg * (1metric ton / 1000kg) = 2.178x10⁴ metric tons
Predict the reactants of this chemical reaction. That is, fill in the left side of the chemical equation.
______ + Cacl2 → H2O
Answer: [tex]Ca(OH)_2+2HCl\rightarrow CaCl_2+2H_2O[/tex]
Explanation:
Neutralization is a chemical reaction where an acid reacts with a base to form salt and water.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side.
The balanced chemical equation will be:
[tex]Ca(OH)_2+2HCl\rightarrow CaCl_2+2H_2O[/tex]
Thus the reactants are calcium hydroxide [tex](Ca(OH)_2[/tex] and hydrochloric acid [tex](HCl)[/tex]
In exothermic reactions, the system
in energy.
energy, while the surroundings
*
absorbs, increase
absorbs, decrease
releases, increase
releases, decrease
Answer:
releases, increase
Explanation:
The total energy of products in an Exothermic reaction is less compare to
total energy of the reactants. As a result of these the enthalpy becomes negative, then there is release of heat to the surroundings, which increase the energy of the immediate surroundings inform of heat. Hence the system release energy while the surroundings energy increase.
Which of the following is an ionization reaction?
a. H2SO4 (aq) + Ca(OH)2 (aq) → CaSO4 (s) + 2 H2O (l)
b. NH3 (aq) + H2O (l) ⇋ NH4+ (aq) + OH– (aq)
c. CH3COO– (aq) + H2O (l) ⇋ CH3COOH (aq) + OH– (aq)
d. None of these
e. H2O (l) + H2O (l) ⇋ H3O+ (aq) + OH– (aq
Answer:
d
Explanation:
2
A student put 25.0 cm of dilute hydrochloric acid into a conical flask.
The student added 2.5g of solid sodium carbonate and measured the change in temperature of
the mixture.
Which apparatus does the student need to use to obtain the most accurate results?
A balance, measuring cylinder, thermometer
B balance, pipette, stopwatch
C balance, pipette, thermometer
D
burette, pipette, thermometer
Answer:
A balance, measuring cylinder, thermometer
Explanation:
In this experiment, three things are really required and they are;
A balance Measuring cylinderThermometerA balance is used to measure out the mass of 2.5g of solid sodium carbonate.
A measuring cylinder is used to measure out the 25.0 cm of dilute hydrochloric acid into a conical flask.
Lastly, a thermometer is used to monitor the change in temperature.
The change of energy from one form to another result in _____. Need help please
Answer:
The change of energy form one form to another result in chemical reaction!
IM GIVING 100 POINTS FOR WHOEVER ANSWERS THIS PLS HELP determine which heat transfers below are due to the process of conduction. I) You walk barefoot on the hot street and it burns your toes. II) When you get into a car with hot black leather seats in the middle of the summer and your skin starts to get burned when you touch the seats. III) A flame heats the air inside a hot air balloon and the balloon rises. IV) A boy sits to the side of a campfire. He is 10 feet away, but still feels warm. Question 1 options: I & II III & IV I, II, & IV II, III, IV
Answer:
I and II
Explanation:
Why do we test for free chlorine in drinking water?
Answer:
The presence of free chlorine in drinking water is correlated with the absence of most disease-causing organisms, and thus is a measure of the potability of water
Why is a rotting apple a reaction in which energy is neither absorbed nor released?
A. The chemical energy in the reactants is almost equal to the chemical energy in the products.
B. The chemical energy in the reactants is much greater than the chemical energy in the products.
C. The chemical energy in the reactants is much less than the chemical energy in the products.
( don’t send links, I won’t click them)
please help me please
Answer:
Two advantages are: Its cheap and it is a renewable energy source. Two disadvantages are it's not windy everyday and it will take up a lot of space for windmills.
Explanation: