Answer:
The mass of K₂Cr₂O₇ needed to create a saturated solution in 400 grams of water at 50°C is 120 grams
Explanation:
To answer the question, we will be required to know the solubility of potassium dichromate, K₂Cr₂O₇ in H₂O at 50°C
From the solubility curve, we have, 30 g of K₂Cr₂O₇ will be required to create a saturated solution in 100 g of at 50°C. Therefore, the amount of K₂Cr₂O₇ that will be required to create a saturated solution in 400 g of water, is given by the following equation;
[tex]400 \times \frac{30 \, g \ K_2Cr_2O_7}{100g \ H_2O} = 120 \, g[/tex]
Therefore, the mass of K₂Cr₂O₇ needed to create a saturated solution in 400 grams of water at 50°C = 120 grams.
Answer:
Approximately 128 g of K₂Cr₂O₇ will saturate 400 g of water.
Explanation:
From Literature and solubility curves, the solubility of K₂Cr₂O₇ at 50°C was obtained to be approximately 32 g/100 mL.
Solubility of K₂Cr₂O₇ in water at 50°C = 32 g/100 mL of water
So, how much K₂Cr₂O₇ will dissolve in 400 g of water?
Density of water = 1 g/mL
So, 1 g of water = 1 mL of water
400 g of water = 400 mL of water.
So, if 100 mL of water dissolves 32 g of K₂Cr₂O₇
400 mL of water will dissolve (32 × 4) g of K₂Cr₂O₇, that is, 128 g of K₂Cr₂O₇.
Hope this Helps!!!!
Which of the following did Antoine Lavoisier correctly characterize as an element? light silicone dioxide mercury
Answer: mercury
Explanation: I looked up the answer to your question.
Answer:
Mercury
Explanation:
I did this question and I got it right.
what is the diffrence between displacement ans double displacement reactions write equations for these reactions
Answer:
Single Displacement reaction
In a displacement reaction, a more reactive element replaces a less reactive element from a compound.
Change in colour takes place with no precipitate forms.
Metals react with the salt solution of another metal.
Examples:
2KI + Cl2 → 2KCl + I2
CuSO4 + Zn → ZnSO4 + Cu
Double displacement reaction
In a double displacement reaction, two atoms or a group of atoms switch places to form new compounds.
Precipitate is formed.
Salt solutions of two different metals react with each other.
Examples:
Na2SO4 + BaCl2 → BaSO4 + 2NaCl
2KBr + BaCl2 → 2KCl + BaBr2
Hope this helps...Please Mark as Brainliest!!
The Sun is a constant supply of energy to Earth.
A. True
B. False
Which is the molar mass of Calcium?
Answer:
40.078 u
Explanation:
Calculate the molar mass of ammonium chloride
Answer:
53.491 g/mol
Explanation:
Create the chemical compound and find each individual element's molar mass. Lastly, add them up.
What is the molarity of a 50.0 ml aqueous solution containing 10.0 grams of table sal, Nacl?
Answer:
The molarity of a 50.0 ml aqueous solution containing 10.0 grams of table sal, Nacl, is 3.42 [tex]\frac{moles}{L}[/tex]
Explanation:
Molarity is a unit of concentration based on the volume of a solution and is defined as the number of moles of solute per liter of solution. Then, the molarity of a solution is calculated by dividing the moles of the solute by the liters of the solution.
[tex]Molarity (M)=\frac{number of moles of the solute}{volume of the solution}[/tex]
Molarity is expressed in units ([tex]\frac{moles}{liter}[/tex]).
Then you must know the amount of moles of the NaCl solute. For that it is necessary to know the molar mass. Being:
Na: 23 g/moleCl: 35.45 g/molethe molar mass of NaCl is: 23 g/mole + 35.45 g/mole= 58.45 g/mole
Then a rule of three applies as follows: if 58.45 grams are present in 1 mole of NaCl, 10 grams in how many moles will they be?
[tex]moles=\frac{10 grams*1 mole}{58.45 grams}[/tex]
moles= 0.171
So you know:
number of moles of solute= 0.171 molesvolume= 50 mL= 0.05 LReplacing in the definition of molarity:
[tex]Molarity (M)=\frac{0.171 moles}{0.05 L}[/tex]
Solving:
Molarity= 3.42 [tex]\frac{moles}{L}[/tex]
The molarity of a 50.0 ml aqueous solution containing 10.0 grams of table sal, Nacl, is 3.42 [tex]\frac{moles}{L}[/tex]
Explain on any two materials that you would expect to use for the wheelchair (both back support and
arm support) with less generation of heat during the hot summers.
Answer:
In the backrest use materials where it is easy to clean and where they do not absorb fluids, in this way it would be cooler, such as an ecological leather simulator.
And in the armrest as well, but in both areas we must not rule out that if or if it should have even a minimum of padded surface so that the patient or the person who spends most of the day in the wheelchair does not suffer from joint pain.
Explanation:
Some wheelchair factories also implement modern chairs where they are made of stainless steel structures lined with padded material with perforated fabrics that allow breathing and aeration of body areas that have contact with the fabric.
Which of these conclusions is correct about P and Q in the diagram?
P represents the land and Q represents the ocean.
P represents the ocean and Q represents the land.
P represents the land and Q represents the atmosphere.
P represents the atmosphere and Q represents the ocean.
Answer:
P represents the atmosphere and Q represents the ocean.
Explanation:
A radioactive isotope has a half life of 25 minutes. How many half lives have occurred after 175 minutes?
5
6
7
8
Will give Brainliest
Answer:
7
Explanation:
The enthalpies of formation of the compounds in the combustion of methane, , are CH4 (g): Hf = –74.6 kJ/mol; CO2 (g): Hf = –393.5 kJ/mol; and H2 O(g): Hf = –241.82 kJ/mol. How much heat is released by the combustion of 2 mol of methane? Use .
Answer:
The amount of energy released from the combustion of 2 moles of methae is 1,605.08 kJ/mol
Explanation:
The chemical reaction of the combustion of methane is given as follows;
CH₄ (g) + 2O₂ (g) → CO₂ (g) + 2H₂O (g)
Hence, 1 mole of methane combines with 2 moles of oxygen gas to form 1 mole of carbon dioxide and 2 moles of water vapor
Where:
CH₄ (g): Hf = -74.6 kJ/mol
CO₂ (g): Hf = -393.5 kJ/mol
H₂O (g): Hf = -241.82 kJ/mol
Therefore, the combustion of 1 mole of methane releases;
-393.5 kJ/mol × 1 + 241.82 kJ/mol × 2 + 74.6 kJ/mol = -802.54 kJ/mol
Hence the combustion of 2 moles of methae will rellease;
2 × -802.54 kJ/mol or 1,605.08 kJ/mol.
Answer: answer is C
Explanation:
Just took the test
How many senses does the human body have?
O A. 3
B. 5
Answer:
B
Explanation:
sight, hearing, smell, taste and touch
Answer:
Most easiest answer..
There are 5 senses in human body.☺️
How many times more acidic is a pH of 2 than a PH of 7?
Answer: 10 times more
Explanation:
The element hydrogen has the highest specific heat of all elements. At room temperature, hydrogen's specific heat is 14.30 J/g •°C. If the temperature of a 340.0 g sample of hydrogen is to be raised by 30°C, how much energy will have to be added to the hydrogen?
Answer:
THE ENERGY NEEDED TO BE ADDED TO RAISE THE TEMPERATURE BY 30°C IS 145, 860 J
Explanation:
The energy needed can be calculated by using the heat formula, which is;
Heat = m c ΔT
m = mass of the hydrogen = 340 g
c = specific heat capacity of hydrogen at room temperature = 14.30 J/g°C
ΔT = change in temperature = 30°C
Heat =?
So therefore,
Heat = 340 * 14.30 * 30
Heat = 145860 J
The energy needed to be added to the hydrogen to bring the mass of 340 g to an increased temperature of 30°C is 145, 860 J or 145.86kJ
How many moles of O2 are needed to react completely with 35.0 mol of 10 points
FeCl3? *
4FeCl3 + 302 — 2Fe2O3 + 3Cl2
A) 26.3 mol
B) 46.7 mol
C) 23.3 mol
D) 10.0 mol
A child has a balloon in his house in the air conditioning. He goes outside with the balloon on a hot day. What happens to the temperature of the gas and volume of the balloon?
Answer:
There would be an increase in temperature and corresponding increase in the volume of the balloon
Explanation:
Charles law is been here
Charles law states that the volume of a given mass of gas is directly proportional to the temperature in Kelvin, provided that the pressure on the gas is kept constant. Mathematically Charles law can be represented thus;
V∝ T
Where V is the volume of the gas and;
T is the temperature.
Relating Charles Law to the question
The child moved outside from the room, constant atmospheric pressure is maintained.The temperature of the room is lower than the temperature outside.From Charles law postulation, there would be an increase in volume because of the increased temperature, since our pressure is same.
If a body was lying on their back when they died, and was moved to their front after 12 hours, where would one see the skin discoloration from pooling blood?
Answer:the parts of the body which is nearest to the ground ie thier back will show discoloration
Explanation:
If the body remains at a position for long hours, the parts of the body which is nearest to the ground can develop a skin discoloration as a result of pooling of blood in the tissues and this is called livor mortis, which tends to be permanent from 8Hours upwards.
What are three examples of acid-base reactions in cooking
Answer:
Lemon juice baking soda and vinegar
Explanation:
What happens when kmno4 is heated
Answer:
kmno4 is heated => k2mno4 + mno2 + o2
Hope this helps!
:)
What pH does an acid have?
Answer:
The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic
Explanation:
Addition of _____________ to pure water causes the least increase in conductivity
organic molecules
because organic molecules does not dissociate in water
A balloon containing N2 has 1.70 moles and occupies 3.80L. What will the volume be if the number of moles is increased to 2.60moles?
Help me please
Answer:
5.81L
Explanation:
N1 = 1.70 moles
V1 = 3.80L
V2 = ?
N2 = 2.60 moles
Mole - volume relationship,
N1 / V1 = N2 / V2
V2 = (N2 × V1) / N1
V2 = (2.60 × 3.80) / 1.70
V2 = 9.88 / 1.70
V2 = 5.81 L
The volume of the gas is 5.81L
Answer the questions using the drop-down menus.
Which is the independent variable in this experiment?
Which is the dependent variable in this experiment?
Which is a controlled variable in this experiment?
In the experiment to measure the heat absorbed by a material placed in
the Sun, we have;
The independent variable is either the angle of insulation or the type of materialThe dependent variable is the temperature of the materialThe controlled variable is the type of material when the angle of insulation is the independent variable and vice versaWhat differentiates the given experimental variables?The possible experiment is with regards to the factors that influence energy from the Sun
The factors investigated are;
The type of material and the angle of lighting (insulation) affects the absorption of heat
The independent variable is the variable that is the cause of the effect
measured in the experiment.
It is the variable that the researcher has control over or controls and
varies during the experiment to produce the measured effect.
In the above experiment, the independent variable are either ;
The angle of insulation or the type of material respectivelyThe dependent variable is the variable that is under test or that is being measured.
In the above experiment the dependent variable is the temperature of the material which can be measuredThe controlled variable is the variable that remains the same or is held
constant during the experiment and can be used as reference to
compare the dependent variable.
In the experiment, the controlled variable are either;
The type of material when the angle of insulation is the independent variable or vice versaLearn more about independent and dependent variables here:
https://brainly.com/question/3764906
Answer:
angle of light
temperature of material
type of material
Explanation:
E d g e 22 !
what is the compound of scI2
Answer:
sulfur dichloride
Explanation:
SCl2 is the chemical formula for sulfur dichloride. This compound is made of only two elements, so it is a binary compound.
how many number of electrons are in aluminium and nitrogen in their free state?
Answer:
MRCORRECT has answered the question
Explanation:
13 electrons
So... for the element of ALUMINUM, you already know that the atomic number tells you the number of electrons. That means there are 13 electrons in a aluminum atom. you can see there are two electrons in shell one, eight in shell two, and three in shell three.
7 electrons
So... for the element of NITROGEN, you already know that the atomic number tells you the number of electrons. That means there are 7 electrons in a nitrogen atom. Looking at the picture, you can see there are two electrons in shell one and five in shell two.
Which is not a reason that water is used to store spent fuel rods from nuclear power plants?
Water increases the speed of the chain reaction in the fuel rods.
Water protects nuclear power plant workers from the high temperature and radiation of the fuel rods.
Water acts as a radiation shield to reduce the radiation levels.
Water cools the spent rods.
Answer:
I believe the answer would be A
Analysis: The limiting reactant(s) appeared to be
because
there is nothing with which it can react
Explanation:
The limiting reactant(s) prevents a reaction from continuing because there is none left.
Why do limiting reactants occur?Identification of the limiting reactant makes it possible to calculate the theoretical yield of a reaction. The reason there is a limiting reactant is that elements and compounds react according to the mole ratio between them in a balanced chemical equation.
How do you get the limiting reactant?The reactant that is consumed first and limits the amount of product(s) that can be obtained is the limiting reactant. To identify the limiting reactant, calculate the number of moles of each reactant present and compare this ratio to the mole ratio of the reactants in the balanced chemical equation.
Learn more about Limiting Reactant(s) here
https://brainly.com/question/14225536
#SPJ2
Copper and silver are two examples of atoms that will form a(n) _____.
metallic bond
ionic bond
covalent bond
none of the above
Answer:
metallic bond but not completely sure
Explanation:
What is an example of a polyatomic ion
Answer: The hydroxide cation (OH -) and the phosphate cation (PO 4 3-) are both polyatomic ions.
Explanation:
Answer:
OH - and PO 4 3- are both polyatomic ions
The metabolic oxidation of glucose, C6H12O6, in our bodies produces CO2, which is expelled from our lungs as a gas.
C6H12O6(aq) + 6 O2(g) → 6 CO2(g) + 6 H2O(l)
Calculate the volume of dry CO2 produced at body temperature (37°C) and 0.960 atm when 24.5 g of glucose is consumed in this reaction.
Answer:
[tex]\large \boxed{\text{21.6 L}}[/tex]
Explanation:
We must do the conversions
mass of C₆H₁₂O₆ ⟶ moles of C₆H₁₂O₆ ⟶ moles of CO₂ ⟶ volume of CO₂
We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.
Mᵣ: 180.16
C₆H₁₂O₆ + 6O₂ ⟶ 6CO₂ + 6H₂O
m/g: 24.5
(a) Moles of C₆H₁₂O₆
[tex]\text{Moles of C$_{6}$H$_{12}$O}_{6} = \text{24.5 g C$_{6}$H$_{12}$O}_{6}\times \dfrac{\text{1 mol C$_{6}$H$_{12}$O}_{6}}{\text{180.16 g C$_{6}$H$_{12}$O}_{6}}\\\\= \text{0.1360 mol C$_{6}$H$_{12}$O}_{6}[/tex]
(b) Moles of CO₂
[tex]\text{Moles of CO}_{2} =\text{0.1360 mol C$_{6}$H$_{12}$O}_{6} \times \dfrac{\text{6 mol CO}_{2}}{\text{1 mol C$_{6}$H$_{12}$O}_{6}} = \text{0.8159 mol CO}_{2}[/tex]
(c) Volume of CO₂
We can use the Ideal Gas Law.
pV = nRT
Data:
p = 0.960 atm
n = 0.8159 mol
T = 37 °C
(i) Convert the temperature to kelvins
T = (37 + 273.15) K= 310.15 K
(ii) Calculate the volume
[tex]\begin{array}{rcl}pV &=& nRT\\\text{0.960 atm} \times V & = & \text{0.8159 mol} \times \text{0.082 06 L}\cdot\text{atm}\cdot\text{K}^{-1}\text{mol}^{-1} \times \text{310.15 K}\\0.960V & = & \text{20.77 L}\\V & = & \textbf{21.6 L} \\\end{array}\\\text{The volume of carbon dioxide is $\large \boxed{\textbf{21.6 L}}$}[/tex]
Write the full symbol for the isotope of oxygen having 8 neutrons.
Answer:
Isotopes are forms of a chemical element that have the same atomic number but differ in mass. 16O → 8 protons + 8 neutrons; a “light” oxygen); The relative amounts are expressed as either 18O/16O or δ 18O Oxygen - 18 (aka 18O → 8 protons + 10 neutrons; a “heavy” oxygen).
