Answer:
Properties of transition elements
they are all metals and that most of them are hard, strong, and lustrous, have high melting and boiling points, and are good conductors of heat and electricity.
what is the difference between isotopes and allotrope not more than three line
Answer:
An allotrope is one way that atoms can be arranged in a solid. An isotope is one way that protons and neutrons can form the same atomic element.
Most of the matter making up the earth is composed of
A. gases
B. compounds
C. mixtures
Most of the matter making up earth is composed of compounds. I think
In an exothermic the change in enthalpy is usually
Positive, because the potential energy of the reactants is higher than the potential energy of the products
Neutral, because the potential energy of the products and reactants cancel each other out.
Negative, because the potential energy of the reactants is higher than the potential energy of the products
Positive, because the potential energy of the reactants is lower than the potential energy of the products
Answer:
Negative, because the potential energy of the reactants is higher than the potential energy of the products
Explanation:
Exothermic reaction is a reaction in which heat is released to surrounding. This is due to the fact that the heat content of the reactant is higher than the heat content of product thus producing a negative enthalpy change (ΔH) i.e
Enthalpy change = Heat of product – Heat of reactant
ΔH = Hp – Hr = negative
Considering the options given in the question above, the correct answer is:
Negative, because the potential energy of the reactants is higher than the potential energy of the products
A compound is composed of 53.33%carbon, 11.11%hydrogen and 35.56%oxygen. If the molecular mass of the compound is 90, what is the molecular formula of this compound?
A student transfers a gas at STP from a 11.0 L tank to a 25.0 L tank. If the pressure
remains constant, what is the new temperature?
. Consider a sample of oxygen gas at 27° C with a volume of 9.55L at a pressure
Answer:620 k
Explanation:
Mr. Whiteman has two stock solutions of sulfuric acid (H2SO4) in the supply closet: 12.1 M and 6.0 M. If he wants to make 10.0 mL of a 1.0 M solution, which stock solution makes more sense to use? Justify with two calculations.
Answer:
12.1-M requires less volume of stock solution.
Explanation:
Hello there!
In this case, according to the foundations of dilution processes, it turns out convenient to remember that the moles of the solute before and after the dilution remains the same; for that reason we use the following equation:
[tex]M_1V_1=M_2V_2[/tex]
Relating the initial and final molarities and volumes. Now, it is seen that V2 is 10.0 mL and M2 is 1.0 M, which means that if we solve for V1 for 12.1 M and 6.0 M, we obtain the following volumes:
[tex]V_1=\frac{M_2V_2}{M_1} \\\\V_1^{12.1M}=\frac{1.0M*10.0 mL}{12.1M}=0.826mL\\\\V_1^{6.0M}=\frac{1.0M*10.0 mL}{6.0M}=1.67mL[/tex]
Therefore, since the 12.1-M solution requires less volume of stock solution, it makes sense to use this one as the initial solution.
Best regards!
Nitrous acid is classified as an Arrhenius acid because HNO2 contains
1. OH-ions
2. 02-ions
3. NO2-ions
4. H+ ions
4) H+ions is your answer , good morning , have a great day ahead.
how many grams of AgNO3 (MM=169.87) are needed to prepare 0.125 M solution in 250 mL of water?
a. 0.5 g
b. .03 g
c. 5.3 g
d. 84.9g
Answer:
Correct answer-C 5.3g
Explanation:
Molarity = no. of moles of solute/ volume of of solution in litre
olarity = no. of moles of solute/ volume of of solution in litreno of moles of solute = 0.125×0.25=0.03125
olarity = no. of moles of solute/ volume of of solution in litreno of moles of solute = 0.125×0.25=0.03125one mole AgNO3 weighs 169.87 gm,
olarity = no. of moles of solute/ volume of of solution in litreno of moles of solute = 0.125×0.25=0.03125one mole AgNO3 weighs 169.87 gm,so the mass of 0.03125 moles of AgNO3 = 0.03125×169.87= 5.3084g
The grams of AgNO₃ are needed to prepare 0.125 M solution in 250 mL of water is 5.3 grams.
How do we calculate mass from moles?Moles is a unit which is used to define any amount and it is calculated as:
n = W/M, where
W = required mass
M = molar mass
Given molarity of AgNO₃ = 0.125 M
Volume of water = 250mL = 0.25L
moles (n) from the molarity (M) will be calculated as:
n = M × V
n = (0.125)(0.25) = 0.0312 moles
Now we calculate the mass of AgNO₃ by using the above formula as:
W = (0.0312mol)(169.87g/mol)
W = 5.30 g
Hence option (c) is correct.
To know more about moles, visit the below link:
https://brainly.com/question/15374113
How many grams is 2.40 x 1023 molecules of N,O,? (5 pts)
PLS HELP ASAP
Answer:
30.26 grams of N₂O₃
Explanation:
Divide by Avogadro's number. This leaves you with the number of moles. Then, multiply by the molar mass of N₂O₃
In chemical reactions, the number of atoms in the product is ________________.
A. the same as the number of atoms in the reactants
B. less than the number of atoms in the reactants
C. greater than the number of atoms in the reactants
D. the same as the number of molecules in the reactants
Answer:
A
Explanation:
2NaCl ---> 2Na + Cl2
What are the atoms of the products
Answer: ...
Explanation:
Sodium, chlorine
Answer:
2Na = 2 Sodium [has 2 atoms]
Cl2 = Dichlorine (Chlorine) [has 2 atoms]
Is this what you wanted?? I'm not entirely sure if this is the answer you were looking for.
Where do we get our energy from ?
Answer:
energy
Explanation:
Pls help really need it pls
8. Of what importance is a smoker to a person keeping bees?
Answer:
they help to calm the bees when the person keeping the bees inspects there hives.
If I add 25mL of water to 125 mL of 0.25 M NaOH solution, what will the molarity of the diluted solution be?
Answer:
0.208333 M
Explanation:
M2=M1V1/V2=(0.25 M)(125mL)/(125mL+25 mL)= 0.208333 M
One major problem with wind and solar energy is that they are conditional. Explain how hydroelectric pumped storage could be used to eliminate this
obstacle? *
Link to the article https://thinkprogress.org/the-inside story-of-the-worlds-biggest-battery-and-the-future-of-renewable-energy-8984c81283c/
Answer:
Hydroelectric pumped storage can be used to eliminate the conditional nature of wind and solar energy. At times of peak production of energy from either solar or wind (during summer and windy days), the excess electrical energy produced can be stored using hydroelectric pumped storage methods. When conditions no longer favour energy production from either wind or solar sources, these stored energy can then be regenerated for use.
Explanation:
Pumped-storage hydroelectricity is a type of hydroelectric energy storage used by electric power systems to store excess electrical power during periods of low demand for later release at periods when demand for energy rises again. It stores energy in the form of gravitational potential energy of water, pumped from a lower level reservoir to a higher level reservoir.
At times of low electrical demand, excess generated energy is used to pump water into the upper reservoir. When there is higher demand, water is released back into the lower reservoir through a turbine, generating electricity.
This form of energy storage is useful in circumventing the conditional nature of renewable energy sources such as wind and solar energy. At times of peak production of energy from either solar or wind (during summer and windy days), the excess electrical energy produced can be stored using hydroelectric pumped storage methods. When conditions no longer favour energy production from either wind or solar sources, these stored energy can then be regenerated for use.
Commercially available concentrated hydrochloric acid is 37.0% w/w HCl. Its density is 1.18g/ml. Calculate the molarity of concentrated HCl?
Answer:
M = 12.0M
Explanation:
Hello there!
In this case, according to the given by-mass percent of HCl, which can be set up in terms of mass of HCl over mass of solution, we can calculate the molarity, by multiplying by the density to get the mL's of solution and further convert to liters. Moreover, the molar mass of HCl (36.46 g/mol) must be also used to calculate the moles, since molar units requires moles of solute and liters of solution as shown below:
[tex]M=\frac{37.0gHCl}{100g\ sln}*\frac{1.18g\ sln}{1mL\ sln}*\frac{1000mL\ sln}{1L \ sln}*\frac{1molHCl}{36.46gHCl}\\\\M= 12.0M[/tex]
Best regards!
What is the percent by mass concentration of 1000 ml of a solution (d=1.5 g/ml) that contains 50 g of solute in it?
Answer: The percent by mass concentration is 33.3 %
Explanation:
Mass percent is the ratio of mass of solute to the mass of solution in terms of percentage.
mass of solute = 50 g
mass of solution = [tex]{\text {density of solution}}\times {\text {volume of solution}}=1.5g/ml\times 1000ml=1500g[/tex]
Mass percentage = [tex]\frac{50g}{1500g}\times 100\%=33.3\%[/tex]
Thus percent by mass concentration of 1000 ml of a solution (d=1.5 g/ml) that contains 50 g of solute in it is 33.3 %
If you use 65.34 g of Al2S3, how many grams of AICl3 can be produced?
Answer:
sorry po
indi ko po maintindihan
What is the best common way to convert fossil fuels into energy?
a. oxidation
b. reaction
c. combustion
d. neutralization
In a solution, litmus is blue. The pH of the solution could be
1. 10
2. 2
3. 3
4. 4
Answer:
1. 10
Explanation
when litmus paper is blue that means the solution is basic and 10 on the pH scale is the most basic out of all your options
What is the main way energy from the Sun moves around Earth?
O
O A.
From the atmosphere
O
B.
From human energy
O
C.
From the ocean currents
Answer:
All of the energy from the Sun that reaches the Earth arrives as solar radiation, part of a large collection of energy called the electromagnetic radiation spectrum. Solar radiation includes visible light, ultraviolet light, infrared, radio waves, X-rays, and gamma rays. Radiation is one way to transfer heat.
9) What is the density of the gold rock with a mass of 386 grams and has a volume of 20 cubic centimeters?
O 0.193 g/cc
O 193 g/cc
O 1.93 g/cc
19.3 g/cc
Answer:
density= mass/volume
hence density of gold rock
= 386/20
=19.3 g/cc
HELP !
The provided balanced equation applies to the reaction that takes place between lithium hydroxide and sulfuric acid. 2LiOH + H2SO4 -> Li2SO4 + 2H2O .
If the reaction begins with 26.7 grams of lithium hydroxide (LIOH) and 164.08 grams of suite acid (H2SO4.), how many grams of lithium sulfate (Li2SO4,) is produced? Assume 100% yield . Round your answer to the nearest tenth of a gram .
Answer:
60g or 61.28g
Explanation:
Trust me on this I had the same problem as you
On a hot day, a student places a glass of cold lemonade on a table outdoors. After a few minutes, water droplets have formed on the outside of the glass.
Is energy absorbed or released by the cold lemonade? Explain your answer.
Compare average kinetic energy for the air molecules and lemonade molecules when the student first places the lemonade outdoors. Explain your answer.
Explain how and why the water droplets form on the outside of the glass.
Answer:
ye but sdfajkd tryng to play me
Explanation:
Answer:
Vapor is released out of the lemonade because when you place it in a hot it will increase.
Explanation:
How can I express the composition of a solution?
Answer:
It can be expressed in several ways: molarity (moles of solute per liter of solution); mole fraction, the ratio of the number of moles of solute to the total number of moles of substances present; mass percentage, the ratio of the mass of the solute to the mass of the solution times 100; parts per thousand (ppt), grams ...
Explanation:
It can be expressed in several ways: molarity (moles of solute per liter of solution); mole fraction, the ratio of the number of moles of solute to the total number of moles of substances present; mass percentage, the ratio of the mass of the solute to the mass of the solution times 100; parts per thousand (ppt), grams ...
The acidic ingredient in vinegar is acetic acid. The pH of vinegar is around 2.4, and the molar concentration of acetic acid in vinegar is around 0.85 M. Based on this information, determine the value of the acid ionization constant, Ka, for acetic acid.
Answer: The value of acid ionization constant [tex]K_a[/tex] for acetic acid is [tex]1.87\times 10^{-5}[/tex]
Explanation:
[tex]CH_3COOH\rightarrow H^+CH_3COO^-[/tex]
cM 0 0
[tex]c-c\alpha[/tex] [tex]c\alpha[/tex] [tex]c\alpha[/tex]
So dissociation constant will be:
[tex]K_a=\frac{(c\alpha)^{2}}{c-c\alpha}[/tex]
Give c= 0.85 M and [tex]pH[/tex] = 2.4
[tex]pH=-log[H^+][/tex]
[tex][H^=}=c\times \alpha=10^{-2.4}=3.98\times 10^{-3}[/tex]
[tex]K_a=?[/tex]
Putting in the values we get:
[tex]K_a=\frac{(3.98\times 10^{-3})^2}{(0.85-3.98\times 10^{-3})}=1.87\times 10^{-5}[/tex]
Thus the value of acid ionization constant [tex]K_a[/tex] for acetic acid is [tex]1.87\times 10^{-5}[/tex]
Why is it important for the daughter cells to divide a second time in meiosis?
The second division switches parts of matching chromatids to increase genetic variation.
The second division forms four identical cells to ensure that all offspring have the same
The second division sorts chromosomes into cells that are the same as the parent cells.
The second division forms haploid cells that can combine with other haploid cells during fertilization.
Answer:
The second division switches parts of matching chromatids to increase genetic variation.
Explanation:
Meiosis and fertilization create genetic variation by making new combinations of gene variants (alleles).
what happen when a piece of silver metal is added to the copper sulphate solution
Answer:
Explanation:When silver Ag metal is added to copper sulphate CuSO4 solution, no reaction takes place as silver is less reactive than that of copper and cannot displace copper from its solution. Hence, when a piece of silver metal is added to copper sulphate solution there will be no reaction.
Answer:
There will be no reaction
Explanation:
Therefore, when silver Ag metal is added to copper sulphate CuSO4 solution, no reaction takes place as silver is less reactive than that of copper and cannot displace copper from its solution. Hence, when a piece of silver metal is added to copper sulphate solution there will be no reaction.
4.What type of energy is used to fuel the process of photosynthesis and what type is produced in
respiration?
A Light energy is used in photosynthesis and created by respiration.
B ATP is used in photosynthesis, which allows the plant to undergo respiration.
C Light energy is used in photosynthesis, whereas respiration creates the energetic product, ATP.
D Food energy is used in photosynthesis and ATP is produced in respiration.
Answer:
A. light energy is used in photosynthesis and created by respiration