Answer:
A stock or standard solution is a solution in which you accurately know its concentration. You can make stock solutions in the chemistry laboratory or buy from chemical manufacturers. Once you have a stock solution, you can prepare solutions of lower concentration by diluting the concentrated stock solution.
Explanation:
To make the correct volume of stock solution, we should add first solid to a volumetric flask.
What is stock solution?Stock solution is a standard solution in which exact concentration of solute is present in particular volume. It is mainly used in analytical chemistry during the titration process.
During the preparation of stock solution, we should first add solid in the volumetric flask and then little amount of water to dissolve the solid and then finally add water to the required volume. If we first add total volume and then add solid then dissolution of solid may increase volume.
Hence, first we add solid in the volumetric flask.
To know more about stock solution, visit the below link:
https://brainly.com/question/3942978
Un profesor desea preparar una disolución de agua oxigenada al 20%v/v y dispone solamente de 50 cm3 h2o2 ¿qué volumen d disolución deberá preparar? Con procedimiento
Answer:
250cm³ de disolución se deben preparar
Explanation:
El porcentaje volumen volumen (%v/v) se define como el volumen de soluto -En este caso, H2O2- en 100cm³ de disolución.
Se desea preparar una solución que contenga 20cm³ de H2O2 por cada 100cm³
Como solamente se cuenta con 50cm³ de H2O2, el volumen que se debe preparar es:
50cm³ H2O2 * (100cm³ Disolución / 20cm³ H2O2) =
250cm³ de disolución se deben prepararwhat is difference between asexual or sexual reproduction
Explanation:
asexual reproduction involves 1 parent and produces offspring that are genetically identical to each other and parent.
Sexual reproduction involves 2 parents and produces offspring that are genetically unique.
When something is hot , its atom has more energy
True or False
Will mark as brainliest if the answer is correct
1: A50 L balloon is at 4 atm of pressure. What is the volume at 2 atm of pressure?
Answer:
100 L
Explanation:
Use Boyle's Law, p1v1 = p2v2.
p1 = 4 atm
v1 = 50L
p2 = 2 atm
v2 = ?
p1v1 = p2v2
(4 atm) (50L) = (2 atm) (v2)
v2 = (4 atm)(50L) / (2 atm) = 100 L
A solid calcium metal reacts with molecular oxygen.
WORD EQUATION =
CHEMICAL EQUATION =
What is the relative formula mass of a compound?
Answer:
To find the relative formula mass (M r) of a compound, you add together the relative atomic mass values (A r values) for all the atoms in its formula.
Explanation: Find the M r of carbon monoxide, CO. Find the M r of sodium oxide, Na 2O. The relative formula mass of a substance, shown in grams, is called one mole of that substance.
In the unbalanced chemical equation shown below, what is the coefficient of aluminum (AI) metal?
Al(s) + O2(g) → Al2O3(s)
Answer : A. 3
Explanation:
3Al(s) + 3O2(g) → 3Al2O3(s)
This is the right Answer :3
I hope you are having a great day :3
Which of the following statements apply to an ionic bond?
Check all that apply.
O A. It is made of two metal atoms.
B. Electrons are shared equally in it.
O C. It is made of two atoms with a large difference in
electronegativity.
O D. It is made of a positive cation and a negative anion.
Answer:
the result is C and D. those are the ansers
Answer:C & D
Explanation:
Just took the test
A molecule with one lone pair and three bond pair
▪︎Ammonia
▪︎carbon tetrachloride
choose correct option
It's ammonia (NH3).....
Answer:
A molecule with one lone pair and three bond pair
- Ammonia
which of the four substances listed will dissolve in water and why?
Answer:
Sugar, sodium chloride, and hydrophilic proteins are all substances that dissolve in water. Oils, fats, and certain organic solvents do not dissolve in water because they are hydrophobic.
And, water is called the "universal solvent" because it dissolves more substances than any other liquid. ... Water molecules have a polar arrangement of the oxygen and hydrogen atoms—one side (hydrogen) has a positive electrical charge and the other side (oxygen) had a negative charge.
I don't see any options so there i hope it helps .
La rapidez de una reaccio es 0,450 mol/s ¡cuanto tiempo, en segundos, serán necesarios para que se consuman 0,323 mol de reactivos
Answer:
[tex]tiempo=0.72s[/tex]
Explanation:
¡Hola!
En este caso, como podemos observar, la relación entre la rapidez de reaction, las moles y el tiempo de reacción es:
[tex]rapidez=\frac{mol}{tiempo}[/tex]
De este modo, despejamos el tiempo en esta ecuación para obtener:
[tex]tiempo=\frac{mol}{rapidez}[/tex]
Así, reemplazamos la rapidez y moles dadas para obtener:
[tex]tiempo=\frac{0.323mol}{0.450mol/s}\\\\tiempo=0.72s[/tex]
¡Saludos!
The diagram shows the water cycle. At point 4, condensation is occurring. How is water changing?
A) Water vapor (gas) is becoming liquid.
B) Water is being stored in the atmosphere.
C) Liquid water in the atmosphere is becoming a gas.
D) Liquid water from the earth's surface is becoming water vapor (gas)
Answer:
water vapor (gas) is becoming liquid
79.4 grams of C3H8 are consumed with an excess of oxygen in the reaction 1 C3H8 + 5 O2 --> 3 CO2 + 4 H2O. How many moles of oxygen (O2) are consumed in this reaction?How many moles of carbon dioxide (CO2) are formed in this reaction? &
How many moles of water (H2O) are formed in this reaction?
Answer:
II would say there is co2 so i would say 30.4
Explanation:
Hope this helps
5. Determine if a precipitation reaction occurs between aqueous silver nitrate and aqueous calcium chloride. If a
precipitation reaction takes place, write a balanced chemical equation, total ionic equation and net ionic
equation for the reaction. Identify any spectator ions.
a. Balanced chemical equation: (3 marks)
b. Total ionic equation: (2 marks)
C. Net ionic equation: (1 mark)
d. Spectator ions: (1 mark)
Answer:
See Explanation
Explanation:
a) In writing the balanced chemical reaction equation, the number of atoms of each element on the right hand side must be the same as the number of atoms of each element on the left hand side. The balanced reaction equation is;
2AgNO3(aq) + CaCl2(aq) ------> 2AgCl(s) + Ca(NO3)2(aq)
b) The total ionic equation shows all the ions present in the reaction system as follows;
2Ag^+(aq) + 2NO3^-(aq) + Ca^2+(aq) + 2Cl^-(aq) ---->2AgCl(s) + Ca^2+(aq) + 2NO3^-(aq)
c) The net ionic equation shows the ions that really participated in the reaction;
2Ag^+(aq) + 2Cl^-(aq) ---->2AgCl(s)
d) The spectator ions didn't undergo any change from left to right in the reaction equation. They include;
NO3^-(aq) and Ca^2+(aq)
Please help I need on this please and thank you
Explanation:
amount of baking soda = 2.01 g
---> 2.01 g NaHCO3 × (1 mol NaHCO3/84.007 g NaHCO3)
= 0.024 mol NaHCO3
mass of the product = 1.28 g
Possible reactions:
NaHCO3(s) ---> NaOH(s) + CO2(g)
0.024 mol NaHCO3 × (1 mol NaOH/1 mol NaHCO3)
= 0.024 mol NaOH × (39.997 g NaOH/1.mol NaOH)
= 0.96 g NaOH
2NaHCO3(s) ---> Na2O(s) + 2CO2(g) + H2O(g)
0.024 mol NaHCO3 × (1 mol Na2O/2 mol NaHCO3)
= 0.012 mol Na2O × (61.9789 g Na2O)
= 0.73 g Na2O
2NaHCO3(s) ---> Na2CO3(s) + CO2(g) + H2O(g)
0.024 mol NaHCO3 × (1 mol Na2CO3/2 mol NaHCO3)
= 0.012 mol Na2CO3 × (105.9888 g Na2CO3/1 mol Na2CO3)
= 1.27 g Na2CO3
Conclusion:
Based on the mass of the product in the crucible and comparing it with the predicted product mass in different reactions, I conclude that Na2CO3 is the most likely product in the crucible.
Name the layers of the atmosphere and one fact about each layer.
what is the [H+] concentration of a solution with a pH of 3.78
Answer:
[H+] = 1.66 x [tex]10^{-4}[/tex]
Explanation:
To find the [H+] concentration of a solution, we can use the formula:
[tex][H+] = 10^{-pH}[/tex]
Let's plug in the pH.
[tex][H+] = 10^{-3.78}[/tex]
Evaluate the exponent.
[H+] = 1.66 x [tex]10^{-4}[/tex]
Hope this helps!
If 40 grams of NH3 are dissolved in 100 mL of water at 10 degrees Celsius, how many more grams of NH3 would I need to add to make this a saturated solution?
Which one is it?
25 g
30 g
20 g
0 g
can someone help me with these answer becuz im struggling sorry
Answer:
21.8
Explanation:
add both because there both forces are going down
Cu2O + C -> Cu + CO2 balanced equation
Answer:
2Cu2O + C --> 4Cu + CO2
Explanation
The Law of conservation of Mass states You can not destroy or create math in a chemical reaction, meaning you must have the same amount at the beginning and the end. This equation keeps the same amount of atoms on both sides.
Answer: Yes, it is a balanced equation.
Explanation:
https://chemequations.com/en/?s=Cu2O+%2B+C+%3D+Cu+%2B+CO2
This is where I got the answer so you know. Hope this helps :)
What is the molarity of a sodium hydroxide solution if 25 mL of the solution is neutralized by 69.5 mL of 1.5 M HCl?
Answer:
4.17M
Explanation:
m1v1/m2v2=n1/n2
chemical formula is given.
CO→C+O
What does the formula describe?
A.
It describes a mixture being separated by a physical process.
B
It describes an atom being separated by a chemical process.
C
It describes an element being broken down into the atoms from which it was formed.
D
It describes a compound being broken down into the elements from which it was formed.
Answer:
D . It describes a compound being broken down into the elements from which it was formed.
Explanation:
A compound consists of two or more elements chemically combined together in a chemical reaction. The compound carbon monoxide is represented by the chemical symbol, CO. This means that it contains 1 atom of the carbon element and 1 atom of the Oxygen element.
This compound is formed when carbon is directly oxidized in a limited supply of oxygen. In the above reaction, this compound is disintegrated into its individual components, namely, carbon and oxygen.
what is the coefficient for water after the equation is balanced?
Answer:
1
Explanation:
Can you pls answer This question
Answer:
a) pentane
b) 1,3-dimethyl butane
c) 3,4-diethyl-5-methlyl heptane
d) 1,3,5-triethyl-2,4,6-trimethyl cyclohexane
Explanation:
The essence of IUPAC nomenclature is to provide a generally accepted nomenclature for chemical compounds which enables the structure of a compound to be drawn from its name without ambiguity.
In order to name straight chain organic compounds, we have to identify the parent chain and then give numbers to the substituents or locants such that they have the lowest possible numbers in alphabetical order.
The correct names of the organic compounds in the question are;
a) pentane
b) 1,3-dimethyl butane
c) 3,4-diethyl-5-methlyl heptane
d) 1,3,5-triethyl-2,4,6-trimethyl cyclohexane
Which of the following reactions is balanced?
Answer:
D
Explanation:
Because it has equal number of elements on each side of the arrow
Which of the following is NOT one of the three main global climate zones?
A. Tropical
B. Latitude
C. Polar
D.Temprate
how much energy is required to melt 2kg of ice at 0°C?
Answer: Therefore, to melt 2kg of ice 835. 48kJ of heat is required.
Explanation:
I hope this helps!
Orange juice is a mixture of several substances, including water, sucrose, and citric acid. If a scientist studies samples of many brands of orange juice, which finding is most likely?
A. The samples contain the same substances in a variety of proportions.
B. The samples contain the same substances in a fixed proportion.
C. The water in each sample has a unique set of properties.
Answer:
A. The samples contain the same substances in a variety of proportions.
Explanation:
If a gas occupies 2.3 liters at a pressure of 1.9 atm, what will be its volume at a
pressure of 3.8 atm?
Answer:
Option C (1.2 L) is the correct option.
Explanation:
The given values are:
Pressure,
[tex]P_1=1.9 \ atm[/tex]
[tex]P_2=3.8 \ atm[/tex]
Volume,
[tex]V_1=2.3 \ L[/tex]
[tex]V_2=?[/tex]
As we know,
The gas equation is:
⇒ [tex]PV=nRT[/tex]
At constant temperature,
⇒ [tex]P_1 V_1=P_2 V_2[/tex]
or,
⇒ [tex]V_2=\frac{P_1 V_1}{P_2}[/tex]
By substituting the values, we get
⇒ [tex]=\frac{1.9\times 2.3}{3.8}[/tex]
⇒ [tex]=\frac{4.37}{3.8}[/tex]
⇒ [tex]=1.15 \ L[/tex]
or,
⇒ [tex]=1.2 \ L[/tex]
C + O = Co
C + 2O = Co2
law of multiple proportions
sort out
Answer:
"When two or more elements combine to form more than one compound, the mass of one of them, which joins the fixed mass of the other, is in relation to whole numbers and simple" Example: The carbo