You have to make 500 mL of a 1.50 M BaCl2. You have 2.0 M barium chloride solution available. Determine how to make the needed dilution
Answer:
There are needed 375mL of the 2.0M BaCl₂ solution completing to 500mL with water.
Explanation:
We can find with the volume and concentration of the barium chloride the moles of BaCl₂ required. With the moles and the concentration of our stock solution we can know the volume of the 2.0M BaCl₂ solution required as follows:
Moles required:
0.500L * (1.50mol / L) = 0.750 moles BaCl₂
Volume stock solution:
0.750 moles BaCl₂ * (1L / 2.0mol) = 0.375L
There are needed 375mL of the 2.0M BaCl₂ solution completing to 500mL with water.How many moles is 80.0 g of calcium?
Answer:
Here we were given the weight of Ca as 80g
and the atomic mass of carbon is 40u(molar mass)
using the formula
n=W/Mwhere w is weight and m is molar mass
80/40
=2
therefore, there are 2 moles in 80g of calcium
How many moles of H,O must be decomposed to form 200 moles of H,?
24,0 2H +0,
Answer:
300
Explanation:
at least 300 molecules
PLeaseee ITS Timedddd + BrainlIESTT
A 6.50 gram piece of aluminum reacts with an excess of oxygen. use the balanced equation below to determine how many grams of aluminum oxide is formed during this reaction.
4 Al + 3 O2 --> 2 Al2O3
a. 662.7 grams of Al2O3
b. 6.1 grams of Al2O3
c. 24.6 grams of Al2O3
d. 12..3 grams of Al2O3
Answer:
d. 12.3 grams of Al2O3
Explanation:
The balanced equation in this question is as follows:
4Al + 3O2 → 2Al2O3
In this equation above, 4 moles of Al produces 2 moles of Al2O3
However, the moles of Al2O3 must first be found using;
mole = mass/molar mass
Molar mass of Al = 27g/mol
mole = 6.50/27
= 0.241mol of Al.
Hence, if 4 moles of aluminum (limiting reagent) reacts to form 2 moles of aluminum oxide (Al2O3).
Then, 0.241mol of Al will produce (0.241 × 2/4) = 0.241/2 = 0.121mol of Al2O3.
Convert this mole value to molar mass using mole = mass/molar mass
Molar mass of Al2O3 = 27(2) + 16(3)
= 54 + 48
= 102g/mol
mass = molar mass × mole
mass = 102 × 0.121
mass of Al2O3 = 12.34grams.
28)
What is a molecule made from joining together small molecules called monomers?
A)
amino acid
B)
glucose molecule
nucleotide
D)
polymer
Answer:
D [polymers]
Explanation:
The joining of monomers (small molecules) is polymerization.
Complete the equation and indicate if a precipitate forms.
Li+(aq) + Br-(aq) + Pb2+(aq) + NO3-(aq) →
Answer:
Li⁺(aq) + 2Br⁻(aq) + Pb²⁺(aq) + NO₃⁻(aq) → PbBr₂(s) + NO₃⁻(aq) + Li⁺(aq)
A precipitate forms
Explanation:
To solve this question we must know the general solubility rules:
All group 1A (Li, Na, K...) and NH₄⁺ ions are always soluble.
The nitrates (NO₃⁻) and acetates are always solubles.
Cl⁻, Br⁻ and I⁻ are soluble except in the presence of Ag⁺, Pb²⁺, Cu⁺ and Hg₂²⁺
That means in the mixture of ions that we have, the Br⁻ will react with Pb²⁺ to produce PbBr₂(s):
Li⁺(aq) + 2Br⁻(aq) + Pb²⁺(aq) + NO₃⁻(aq) → PbBr₂(s) + NO₃⁻(aq) + Li⁺(aq)An organism that makes or creates their own food?
A. Consumer
B. Producer
C. Decomposer
I think producer
option is A
Answer:
B. Producer
Explanation:
A producer is normally a type of plant which is food for the animals. Decomposers are things that decompose dead living things into nutrients and etc. Consumers are the ones who normally feed on producers in the food web and are small animals.
Ionic bonding, covalent bonding and metallic bonding are similar in that all three result in atoms having octets and greater stability. However, they differ in terms of the types of atoms that participate and whether the electrons are transferred or shared. Describe how ionic, covalent and metallic bonding differ in terms of elements participating in each bond and the way electrons are distributed.
Answer:
ionic --complete transferring
covalent--- sharing of electron
metallic bonding--- occurs between free electrons and metal ions.
Explanation:
In ionic bond, the electrons transfer from one atom to another atom. The atom which loses electrons is known as donor whereas the atom which accept electrons is known as acceptor. In covalent bond, atoms share electrons mutually means both atoms donate their electrons and no one loses their electrons, it can only be shared. Metallic bonding refers to the type of bonding in which electrostatic attractive force present between free electrons and positively charged metal ions.
What is the mass of 925.4 L of hydrogen gas at STP?
Answer:
If this is an idea gas then 1mol takes up 22.4L.
So, knowing how many L you have you can figure out how many mole syou have by doing a simple equation:
[tex]\frac{1mol}{y} =\frac{22.4L}{925.4L}[/tex]
Solve for y.
Then, since you know how many moles you have use the ptable https://ptable.com/#Properties to figure out the mass in grams.
NOTE: The ptable tells you that 1mol of H = 1g.....so this should be an easy calculation :) enjoy
Identify the parts of a wave using the illustration and the function below.
Answer: 1. Crest 2. Trough 3. Wave Length 4. Amplitude
Explanation:
There are 4 mg of lead present in 2000 g of a water sample. What is the
concentration of lead in m?
Answer: 130 ppm Pb
Explanation:
We use parts per million to express the concentrations of solutions that contain very, very small amounts, often called trace amounts, of a given solute.
More specifically, a solution's concentration in parts per millions tells you the number of parts of solute present for every
10
6
=
1
,
000
,
000
parts of solution. You can thus say that a
1 ppm
solution will contain exactly
1 g
of solute for every
10
6
g
of solution.
In your case, you know that you have
38
mg Pb
⋅
1 g
10
3
mg
=
3.8
⋅
10
−
2
.
g Pb
in exactly
300.0 g
=
3.000
⋅
10
2
.
g solution
This means that you can use this known composition as a conversion factor to scale up the mass of the solution to
10
6
g
10
6
g solution
⋅
3.8
⋅
10
−
2
.
g Pb
3.000
⋅
10
2
g solution
=
130 g Pb
Since this represents the mass of lead present in exactly
10
6
g
of solution, you can say that the solution has a concentration of
concentration
ppm
=
130 ppm Pb
−−−−−−−−−−−−−−−−−−−−−−−−−−−−
The answer is rounded to two sig figs, the number of sig figs you have for the mass of lead present in the sample.
Which is the term for the different forms of a gene for a given trait?
Answer:
An allele is a variant form of a gene. Some genes have a variety of different forms, which are located at the same position, or genetic locus, on a chromosome. Humans are called diploid organisms because they have two alleles at each genetic locus, with one allele inherited from each parent.
Does the +2 and -1 make a difference when solving for the Hrxn? What difference does it make?
Answer:
It would be a square plus b square and i am writing just so i can get pionts
Explanation:
What is the mass of sulfuric acid, h2so4, that is contained in 2.0L of a 5.85 M solution ?
A- 1147.44 grams
B- 0.12 grams
C- 11.7 grams
D- 98.07 grams
Answer:
A. 1147.44 grams
Explanation:
Multiply volume by molarity to get the moles of solution.
5.85 M = mol/2.0 L
mol = (5.85 M)(2.0 L)
mol = 11.7
There is 11.7 moles of H2SO4.
Convert to grams with molar mass.
11.7 mol H2SO4 x (98.076 g/1 mol) = 1147.49 g
Closest answer is A, 1147.44 g.
What would cause entropy to increase in a reaction?
A. The products becoming more spread out
B. The products forming an ordered pattern
C. The products forming fewer molecules
D. The products forming a more rigid structure
i think A but if I'm wrong sorry
then if increasing then becoming spread out so letter A
(GIVING BRAINLIEST) Which of the following is a good source of carbohydrates?
pears
meat
eggs
fish
Answer:
I would choose pear fruits are a good source of carbohydrates hopefully its right sorry if its not
Answer: Fruit
Fruits have a lot of carbohydrates in them :) Hope this helped!
How is it possible for scientists to know the composition of stars without traveling to the star?
Answer:
One of the most common methods used today to determine the composition of stars is spectroscopy.
Explanation:
Spectroscopy is the study of the interaction between matter and electromagnetic radiation as a function of the wavelength or frequency of the radiation.
A car accelerates away from the starting line at 3.6 m/s2 and has the mass of 2400 kg. What is the net force acting on the vehicle?
__ Newtons ??
Answer:
8640 NExplanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question we have
net force = 2400 × 3.6
We have the final answer as
8640 NHope this helps you
which one is correct for #4 ??
Answer:
The answer of this question is A
Answer: B is the right
Explanation:
Balance the equation :
CoBr3 + CaSO4
please define how many atoms each element contain
Answer:
im not 2100][dskcmaln,NMCS KHJBXsjk[pl,;maxkcjxnxxxxxxxxxxxxxas'j
Explanation:
mnkc
Which boundary or zone adds new material to the lithosphere (the hard outer crust of the Earth)
Answer:Divergent Boundaries(or Boundary)
Explanation:took the test and got it right
which of the following elements has the lowest first ionization eneygy A, potassium B, sodium C, calcium D, Argon
Answer:
Argon
Explanation:
Because, it is positioned down on the periodic table
Answer:
Argon
Explanation:
Put the following in order from largest to smallest.
Chromosome, gene, nucleus, cell, DNA
Answer:
cell, nucleus , chromosome, DNA, gene
3. What is the density of a 100 grams (g) box that displaces 20 mL of water?
Answer: the density is 997 kg
Explanation:
What is one end of a magnetized compass's needle attracted to?
Answer: The red on is attracted to The north pole
Explanation:
Select all that apply.
Which of the following are density labels?
Okg
L
09
m
og
mL
g
9. Which of the following would increase the
validity of Experiment 2?
A. Testing magnets with a volume less
than 0.04
B. Testing magnets made of iron instead
of ceramic
C. Testing generators with larger
vibrations
D. Testing a generator with coils fewer
than 2050
.
Starting with a 7. 0 x 10-5 M. Allura Red stock solution you will need to calculate the volumes required to prepare 10.00 mL solutions of 3.5 x 10-5 M, 2.8 x 10-5 M, 2.1 x 10-5 M, 1.4 x 10-5 M, and 3.5 x 10-6 M before coming to lab. What volume of the stock solution will be required to prepare 10.00 mL of a 2.1 x 10-5 M solution of Allura Red?
Answer:
1) 5.0 mL, 4.0 mL, 3.0 mL and 2.0 mL respectively.
2) 3.0 mL
Explanation:
Hello there!
1) In this case, by considering that the equation we use for dilutions contain the initial and final concentrations and volumes:
[tex]C_1V_1=C_2V_2[/tex]
For the first four solutions, we compute the volume of the stock one (V1) as shown below:
[tex]V_1=\frac{C_2V_2}{C_1}[/tex]
Thus, we obtain:
[tex]V_1^1=\frac{3.5x10^{-5}M*10.00mL}{7.0x10^{-5}M} =5.0mL\\\\V_1^2=\frac{2.8x10^{-5}M*10.00mL}{7.0x10^{-5}M} =4.0mL\\\\V_1^3=\frac{2.1x10^{-5}M*10.00mL}{7.0x10^{-5}M} =3.0mL\\\\V_1^4=\frac{1.4x10^{-5}M*10.00mL}{7.0x10^{-5}M} =2.0mL[/tex]
2) In this case, for a final concentration of 2.1x10-5 M and a volume of 10.00 mL, the volume of the stock solution would be:
[tex]V_1=\frac{2.1x10^{-5}M*10.00mL}{7.0x10^{-5}M} =3.0mL[/tex]
Best regards!
What happens in a redox reaction?
Which is the metric standard for measuring energy?
Answer:
Calorie
Explanation:
This can mesure thermal energy