Given a 0.5 M stock solution of aqueous NaCl, how much of the stock solution would you need to make a 50 mL sample of 0.25 M aqueous NaCl solution? How much water would you need to add to the NaCl solution?
Answer:
25 ml of stock
Explanation:
Molarity x Volume of Concentrated Stock = Molarity x Volume of Diluted Stock
=> Mc x Vc = Md x Vd => (0.5M)(x) = (0.25M)(50 ml)
=> x = Vc = (0.25M x 50 ml) / (0.50M) = 25 ml of stock
Which of the following descriptions is correct?
А. a mixture consists of two or more pure substances which can only be separated by chemical methods
B. a colloid is a 'cloudy' mixture containing particles which will not easily settle out when the colloid is left standing
C. a solution consists of a solvent dissolved in a solute
D. a suspension contains particles which will not settle out if the suspension is left standing
An exothermic reaction
In an endothermic reaction, the energy of the products is
the energy of the reactants.
Activation energy is
the potential energy of the products.
Answer:
An exothermic reaction
✔ produces energy
.
In an endothermic reaction, the energy of the products is
✔ more than
the energy of the reactants.
Activation energy is
✔ always greater than
the potential energy of the products
Answer:
Produces energy
More than
Always greater than
Explanation:
why are noble gases considered the most stable elements
Answer:
they have the maximum number of valence electrons their outer shell can hold.
Explanation:
help MEEEEE!!!!!!!!!!!
Answer:
Equation
Mark as brainlist
Answer:
equation
Explanation:
chemical changes can be shown in an equation/reaction because you can see products and reactants.
Please give me brainliest
What is the cation in KF?
Answer:
K, or Potassium
Explanation:
Q1. Consider respiration, one of the most common chemical reactions on earth occur according
to the reaction:
C6H1206 +602 = 6CO2 + 6H2O + energy
What mass of CO2 forms in the reaction of 25g of glucose with 40g of oxygen?
Answer: First we need to know how many moles of each reactant there are.
C6H12O6 : 25g/180.06g/mol=0.1388mol
O2: 40g/32g/mol=1.25mol
The equation tells us we need 6 moles of O2 for every 1 mole of Glucose.
6 x 0.1388 = 0.8328
So, we have more O2 then needed – it is in excess.
Glucose is the limiting reagent – we use this for the calculation.
The equation tells us we make 6 moles of CO2 for every 1 mole of Glucose
So, we make 0,8328 moles of Carbon Dioxide
Explanation:
In terms of percentages, what are the 3 biggest uses of natural gases?
1) Using Gas In The Home. In our homes, we end up utilizing the material every day.
2) Use In The Industrial Sector. The industrial sector makes similar use of natural gas liquids as a fuel for process heating and raw material to produce chemicals, fertilizers, and hydrogen.
3) Transportation.
Hope this helps. Btw, I love ur pfp!
Answer:
1) Using Gas In The Home. In our homes, we end up utilizing the material every day. ...
2) Use In The Industrial Sector. The industrial sector makes similar use of natural gas liquids as a fuel for process heating and raw material to produce chemicals, fertilizers, and hydrogen.
3) Transportation.
can someone help me???
Answer:
Waning Crescent
Explanation:
Hope iT Help
Brainliest please
Which statement describes a physical property of copper?
Answer:
Copper is typically a solid and has a coppery, bronzy color. It is a metal and has a relatively high melting point. It has a strong luster and can conduct electricity.
Answer:
RESHAPE BY A FORCE.
Explanation:
1. It can be reshaped by a force. Physical property can be observed and measured without any changes in molecular composition.
2. A physical property is one that can be change without altering the identity of the substance. These set of properties is not concentration dependent they are use to describe matter. Example are: density, solubility, melting point and color and odor. For this case the second option seems to fit the description it can be reshape by force.
What transition energy corresponds to an absorption line at 502 nm?
A. 4.56 x 10-19
B. 1.76 10-19
C. 2.53 x 10-19
D. 3.96 10-19 J
Answer:
D 3.96 10-19J
Explanation:
I took the test
- What happens when a hydrogen atom absorbs a quantum of energy?
the hydrogen moves to an excited state and electrons will move to higher energy levels
calculate the pH of the following
A.0.02mol/L HCI
B. 0.1 mol/L NaOH
Answer:
A.
Explanation:
hope it helps
g Consider (12.5 A) micro-grams of a radioactive isotope with a mass number of (78 B) and a half-life of (32.6 C) million years. If energy released in each decay is 32.6 keV, determine the total energy released in joules (J) in 1 (one) year. Give your answer with three significant figures.
Answer:
Energy released = 18.985 J
Explanation:
The exponential decay of radioactive substance is given by -
N(t) = N₀ [tex]e^{-kt}[/tex]
where
N₀ = initial quantity
k = decay constant
Half life, [tex]t_{1/2} = \frac{ln 2}{k}[/tex]
⇒[tex]k = \frac{ln 2}{t_{1/2} }[/tex]
Given,
N₀ = 12.5 + 3 = 15.5 × 10⁻⁶ gm
[tex]t_{1/2}[/tex] = 32.6 + 18 = 50.6 × 10⁶ years
So,
[tex]k = \frac{ln 2}{50.6 * 10^{6} }[/tex] = 1.361 × 10⁻⁸ year⁻¹
Now,
N(1) = 15.5 × 10⁻⁶ [tex]e^{-1.361*10^{-8} *1}[/tex]
= 15.49999978904
Now,
Substance decayed = N₀ - N(t)
= 15.5 × 10⁻⁶ - 15.49999978904 × 10⁻⁶
= 21.095 × 10⁻¹⁷ kg
⇒Δm = 21.095 × 10⁻¹⁷ kg
So,
Energy released = Δmc²
= 21.095 × 10⁻¹⁷ × 3 ×10⁸ × 3 × 10⁸
= 189.855 ×10⁻¹
= 18.985 J
⇒Energy released = 18.985 J
The oxidation state for Cl is A. -1 as a reactant and +1 as a product B. -1 as a reactant and 0 as a product C. -1 as a reactant and -1 as a product D. +1 as a reactant and +1 as a product
Answer:
no sure
Explanation:
Help me with this plz
Answer:
EVEN DOE IT TOO LATE, ITS B
Explanation:
120 g of KI at 0 °C solution is
Answer:
i dont care to you
Explanation:
cause you are tuyo
solution is 9°5
What ideas do you have about why these ions are so important for life?
Answer:
i dont get it
Explanation:
im small brain and only in 5th grade
In a simple food chain, a frog eats insects and a snake eats the frog. The primary role of the frog in the food chain is?
Answer:
It is clear from the above food chain that the grass occupies the first topic level which consists of producers. The second tropic level consist of primary consumers which is Insect. And the Frog assign the Third tropic level of food chain consisting of secondary consumers.Explanation:
how toxic is uranium
Answer:
Inhaling large concentrations of uranium can cause lung cancer from the exposure to alpha particles. Uranium is also a toxic chemical, meaning that ingestion of uranium can cause kidney damage from its chemical properties much sooner than its radioactive properties would cause cancers of the bone or liver.
Explanation:
Today, there are ____ GMO crops currently produced in the US.
A. 120
B. 10
C. 55
D. 1000
Answer: I think that is 55
Explanation: I hope I help
true or false atoms can be made up of just one type of atom
Answer:
false
Explanation:
A compound has the combined properties of the elements from which it is made. Atoms show the macro properties of an element.
Which location in the diagram above is the Northern Hemisphere experiencing winter?
Location A
Location B
Location C
Location D
Answer:
location b
Explanation:
Answer:
Location D
Explanation:
is true answer
Q13. Which of the following is a balanced chemical equation for the reaction between potassium carbonate soletion and hyelrochlori acid. 1
Answer:
Below
Explanation:
2HCl + K2CO3 -> 2KCl + CO2 + H2O
O
The ester functional group is symbolized as ||
R-C-R
True False
Answer:
False
The ester functional group is not symbolized as R-C-R
Explanation:
The general formula of ester functional group is RCOOR′ where R represents a hydrogen atom or aryl group or an alkyl group while R' represents the alkyl group or an aryl group
Hence, the given statement is false
Can someone please help with this !!!!
Which of the below is not a characteristic of a liquid?
Has a definite volume
Particles are spread far apart
Particles move at a medium speed
Takes the shape of its container
Arctic foxes grow new fur with different seasons. They grow brown fur in the summer and white fur in the winter. These changes are examples of which survival characteristic?
adaptation
hibernation
metamorphosis
migration
Answer:
Adaptation.
Explanation:
The survival characteristic adopted by Arctic foxes during different seasons is called adaptation.
The term adaptation is used to define any behavioral or physical characteristics adopted by animals to help them survive their environment. The survival characteristics in the animal can be categorized into three domains: body parts, body coverings, and behaviors. In Arctic foxes, we see body coverings survival characteristics.
Therefore, option A is correct.
A 10.35 kg block of ice has a temperature of −22.3 °C. The block absorbs 4.696 x 10^6 J of heat. What is the final temperature of the liquid water?
Answer:
: A 10.35 kg block of ice has a temperature of - 22.3 degree C. The block absorbs 4.696 times 10^6 J of heat. What is the final temperature of the liquid water?
Previous question: A 10.35 kg block of ice has a temperature of - 22.3 degree C. The block absorbs 4.696 times 10^6 J of heat. What is the final temperature of the liquid water?
Previous question: A 10.35 kg block of ice has a temperature of - 22.3 degree C. The block absorbs 4.696 times 10^6 J of heat. What is the final temperature of the liquid water?
Previous question: A 10.35 kg block of ice has a temperature of - 22.3 degree C. The block absorbs 4.696 times 10^6 J of heat. What is the final temperature of the liquid water?
Previous question
Explanation:
How do we calculate how fast (speed) Earth is rotating on its arist
speed = distance / time
speed = distance x time
speed = time / distance