Answer:
125 ohms
Explanation:
since they're parallel we do
1/total resistance = (1/250 ohms) + (1/250 ohms)
then you get 2/250 ohms
then you flip it so it's equal to total resistance/1
250÷2= 125
calculate the mass m of 6.50 moles n of kbr m
Answer:
773.51495 grams
Explanation:
1 moles KBr to grams = 119.0023 grams
6.5*119.0023 = 773.51495 grams
The half-life of strontium-90 is about 29 years. How many half-lives have elapsed when 6.25% of
O 1
02
3
оо
The question is incomplete, the complete question is;
The half-life of strontium-90 is about 29 years. How many half-lives have elapsed when 6.25% of a strontium- 90 sample remains in the container?
Answer:
4 half lives
Explanation:
From;
N/No = (1/2)^t/t1/2
N= amount of strontium-90 present at time t
No= amount of strontium-90 originally present
t= time taken
t1/2 = half life of strontium-90
But N= 0.0625No
Hence;
0.0625No/No = (1/2)^t/29
0.0625 = (1/2)^t/29
(1/2)^4 = (1/2)^t/29
4 = t/29
t = 4 × 29
t= 116 years
Hence four half lives have elapsed
Write the complete and net ionic equations for the following reactions. If only the reactants are given, predict the products and balance the equation first.
Explanation:
u can put them in order crossed are spectator ions. hope this helps:)
calculate the oxidation numbers of the elements in this equation
2 Al2O3 → 4 Al + 3 O2
Explanation:
Answer
Open in answr app
The rule used here is that the algebraic sum of the oxidation numbers of all the atoms a molecule is zero.
Al2O32× ( oxidation number of Al)+3× ( Oxidation number of O ) = 0
2× ( Oxidation number of Al) +3(−2)=0
2× ( oxidation number of Al) +6
∴ Oxidation number of Al =+3
A 12 inch object is placed 30 inches in front of a plane mirror
Answer:
12 inches
Explanation:
i got it right in the Same question
the six gas laws ASAP PLS
A scientist formulates the following hypothesis: If plants of the same species
are grown under the same conditions, the amount of fertilizer the plants
receive will affect their growth rate. Which variable will be a responding
variable in the experiment designed to test this hypothesis?
Answer:
Growth rate
Explanation:
The responding variable, also known as the DEPENDENT VARIABLE, is the variable that responds to changes or manipulations made to another variable (independent or manipulable variable) in the experiment. It is the measured variable of an experiment.
According to the hypothesis provided for this investigation, the scientist wants to determine if the amount of fertilizer plants of the same species receive will affect their growth rate when planted in the same condition. This shows that the independent variable is the amount of fertilizer to be used while the RESPONDING VARIABLE OR DEPENDENT VARIABLE is the GROWTH RATE OF THE PLANTS because it responds to the amount of fertilizer.
Geometric isomers have profound effects on the physical properties of compounds. Naturally occurring fatty acids generally adopt a cis geometry. What's one physical property affected by this geometry? (HELP ASAAAP!)
A)
Color
B)
Taste
C)
Smell
D)
Melting point
Answer:
melting point
Explanation:
8)
When an equation is correctly balanced, it must show conservation of
A)
charge but not of mass
B)
mass but not of charge
C)
both charge and mass
D)
neither charge nor mass
Form similar pairs of words.
Boron : B :: Beryllium :
Answer:
Boron : B :: Beryllium :Be
Explanation:
Boron is an element found in group 13 of the periodic table. It has three electrons in its outermost shell hence a valency of 3.
Beryllium is an element in group two of the periodic table. It has a valency of two hence there are two electrons in its outermost shell.
Boron and beryllium are similar words. The symbol of boron is B while the symbol of beryllium is Be.
If you add 25.0 mL of water to 125 mL of a 0.150 M LiOH solution, what will be the molarity of the resulting diluted solution? 0.0450 M LiOH 0.0647 M LiOH 0.125 M LiOH 0.134 M LiOH
Answer:
solute in a fixed volume of solution
Concentration(c) = number of moles of solute(n) / volume of solution (v)
25.0 mL of water is added to 125 mL of a 0.150 M LiOH solution and solution becomes more diluted.
original solution molarity - 0.150 M
number of moles of LiOH in 1 L - 0.150 mol
number of LiOH moles in 0.125 L - 0.150 mol/ L x 0.125 L = 0.01875 mol
when 25.0 mL is added the number of moles of LiOH will remain constant but volume of the solution increases
new volume - 125 mL + 25 mL = 150 mL
therefore new molarity is
c = 0.01875 mol / 0.150 L = 0.125 M
answer is 0.125 M
Explanation:
did this answer got right
Answer:
0.125
Explanation:
Just completed the test and got it correct.
How do catalysts increase reaction rates? *
By increasing the activation energy.
By broadening the energy barrier.
By forming an activated complex with lower energy.
By changing the net thermodynamics of the reaction.
Answer:
By forming an activated complex with lower energy.
Explanation:
When catalyst is added to a reaction , it forms an activated catalyst which has lower activation energy . So initiation of reaction requires less energy and reaction becomes fast .
Hence third option is correct.
The radius of the large cylinder of a hydrolic press
20cm and that of the small cylinderis 5 cm. If a force of 100N is applied on the small piston Calculate the force on the large piston. if the piston of the small cylinder move through a distance of 0.4m through what distance can the large piston be raised
Answer: 1) 400N
2)1.6
Explanation:
1) 5cm = 100N of force
so
20cm=400n
2) 0.4 X 4 = 1.6
Describe two situations in which you observed or performed an energy transformation. For each situation, name the starting form of energy and an ending form of energy.
Answer:
The Sun transforms nuclear energy into heat and light energy.
Our bodies converting chemical energy in our food into mechanical energy for us to be able to move.
An electric fan transforming electrical energy into kinetic energy.
are there other universes ??
Answer:
Some theories say that there is only one universe and that everything is inside the universe and there is nothing outside the universe but some other theories say that there are more Universes which has the opposite copy of all the planets in our universe.
Please answer. Brainliest!
The equation is balanced.
Explanation:The number of P atoms in the reactant side is 4 and the number of P atoms in the product side is also 4.
The number of O atoms in the reactant side is 16 and the number of O atoms in the product side is also 16.
The number of H atoms in the reactant side is 12 and the number of H atoms in the product side is also 12.
These results are in accordance with the law of conservation of mass.
#ILoveChemistry
Which of the following represents an element ? H2O H2 NaCl CaCO3
Answer:
H₂
Explanation:
H₂ is hydrogen in its elemental form.
H₂O, NaCl, and CaCO₃ are all examples of elements added together to create compounds.
PLEASE HELP!!
What is the reduction half-reaction for 2Mg + O2 —> 2MgO?
A) Mg -> Mg2+ + 2e-
B) O2 + 4e- -> 2O2-
C) Mg2+ + 2e- -> Mg
D) 2O2- -> O2 + 4e-
Answer:
O2 + 4e- -> 2O2-
Explanation:
You have to start by assigning the oxidation numbers, which eventually will lead to every atom of oxygen taking 2 electrons and every molecule of oxygen will take 4 electrons.
(you can ignore this explanation, my answer wasn't long enough).
Plz help fast it’s due very soon
8 moles
Explanation:
in the equation 1 mole of methane is reacting with 2 mole of oxygen
if 1 mole is reacting with 2 moles
so 4 mole will react with 2×4 = 8 moles
Answer:
8
Explanation:
beacuse use the molar ratio of ch4 : O2 which is 1:2 so you times 4 by 2
A wheelbarrow can be used to help lift a load, such as a pile of dirt, and then push the load across a distance.
A man pushes a wheelbarrow.
Which simple machines make up a wheelbarrow?
a pulley and an inclined plane
a wheel and axle and a lever
a pulley and a wheel and axle
a lever and a wedge
Answer: it consists of two simple machines: a lever and a wheel and axle. Effort is applied to the lever by picking up the handles of the wheelbarrow.
Explanation:
Answer:
B
Explanation:
B)
Can you guys help!!!
During a certain chemical reaction, the temperature gradually increases.
Which statement best describes this process?
A. It is combustion.
B. It is endothermic.
C. It is a closed system.
D. It is exothermic.
No links!!!
No spams!!
Answer:
D. lt is exothermic is the correct ans
will give u brainliest plzz help
Answer:
4.76 mol / L
Explanation:
The process that takes place is:
Sc₂(C₂O₄)₃ → 2Sc⁺³ + 3C₂O₄⁻²Assuming we have 1 L of the solution, we would have 2.38 moles of Sc₂(C₂O₄)₃.
We then convert 2.38 moles of Sc₂(C₂O₄)₃ into moles of Sc⁺³, using the stoichiometric coefficients:
2.38 mol Sc₂(C₂O₄)₃ * [tex]\frac{2molSc^{+3}}{1molSc_2(C_2O_4)_3}[/tex] = 4.76 mol Sc⁺³Finally we calculate the concentration of scandium ion (Sc⁺³) in mol/L:
4.76 mol Sc⁺³ / 1 L = 4.76 mol/LPLEASE HELPP!!
What is the empirical formula of the compound is C22H44O22
A. CH2O
B. C3H6O3
C. C2H4O2
D. CHO
Answer:
The answer is C
How many significant digits are in the value 0.0050340?
Answer:
6
Explanation:
6, because the number after decimals are considered significant but the 0 after the last number is not significant.
Please help ………………….
Answer:
magnsium po
Explanation:
How many moles of sucrose
are in 5.25x1029 sucrose
molecules? (in scientific notation)
Answer:
8.72 × 10^5 moles
Explanation:
To find the number of moles in 5.25 x 10^29 molecules of sucrose, we divide the number of molecules by Avagadro constant (6.02 × 10²³ molecules). That is;
no. of moles = no. of molecules ÷ 6.02 × 10²³ molecules
In this case of sucrose, no of moles contained is as follows;
5.25 × 10^29 ÷ 6.02 × 10²³
5.25/6.02 × 10^ (29-23)
0.872 × 10^6
= 8.72 × 10^5 moles
Which of the following demonstrates how chemicals can help the environment?
A. Herbicides can get rid of unwanted weeds.
B. Pollutants can be prevented from entering the environment.
C. Pesticides can kill insects that eat garden plants.
D. Lime can be used to adjust the pH in lakes that are too acidic.
To solve this we must be knowing each and every concept related to environment. Therefore, the correct option is option D among all the given options.
What is environment?A basic definition of such an environment is a system that includes all abiotic and biotic components that impact human existence. All flora and animals are biotic components, whereas abiotic components comprise water, sunshine, air, temperature, and so on.
An environment's resources might be any issue, service, or specifics that are beneficial to society and humans. They might be anything that meets the demands of daily living. Lime can be used to adjust the pH in lakes that are too acidic demonstrates how chemicals can help the environment.
Therefore, the correct option is option D.
To know more about environment, here:
https://brainly.com/question/28962722
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How many moles are in 243 grams of Al(OH)3?
Answer:
The answer is 78.003558.
We assume you are converting between grams Al(OH)3 and mole.
You can view more details on each measurement unit:
molecular weight of Al(OH)3 or mol
This compound is also known as Aluminium Hydroxide.
Explanation:
Which prefix indicates a molecule with 2 carbon atoms?
O A. Eth-
O B. Oct-
O c. Hex-
O D. Meth-
The answer is A.Eth-
The prefix indicates a molecule with 2 carbon atoms is eth- and the correct option is option A.
What is IUPAC Nomenclature?
The IUPAC system of nomenclature is a set of logical rules framed which are mainly aimed at giving an unambiguous name to an organic compound.
IUPAC stands for International Union of Pure and Applied Chemistry
A prefix to the name comes before the molecule. The prefix of the molecule's name is based on the number of carbon atoms.
For example, a chain of six carbon atoms would be named using the prefix hex-.
The suffix to the name is an ending that is applied that describes the types of chemical bonds in the molecule.
Therefore, The prefix indicates a molecule with 2 carbon atoms is eth- and the correct option is option A.
Learn more about IUPAC Nomenclature, here:
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Detecta cuál de las siguientes fórmulas estructurales no cumple con la tetravalencia del carbono (formar cuatro enlaces)
El ejercicio completo con las formulas es el siguiente:
cuál de las siguientes fórmulas no cumple con la tetravalencia del átomo de carbono.
a. CH3-CH2-CH2-OH
b. CH3-CH=CH2
c. CH3-CH2=CH2
d. CH3-CH2-CH3
Answer:
La respuesta correcta es la opción C
Explanation:
En la formula C, podemos ver claramente que no se cumple con la tetravalencia del carbono pues al sumar el total de las valencias del carbono nos da 5
CH3 - CH2 = CH2 = Total de valencias del carbono 5
1 + 2+ 2 = 5
Para que la formula sea correcta debe eliminarse un hidrogeno quedando la formula de la siguiente manera:
CH3 - CH = CH2
1 + 1 + 2 = 4