Answer:a scientist would choose to conduct a controlled experiment when it has all the necessary precautions and has the equipment to do so
Explanation:thank you
Plz mark for brainlist
To calculate the atomic mass of an element, the percent
abundance of etch isotope is needed. ?
Answer:
List the known and unknown quantities and plan the problem. Change each percent abundance into decimal form by dividing by 100. Multiply this value by the atomic mass of that isotope. Add together for each isotope to get the average atomic mass
Explanation:
Which of the following best represents a chemical change?
A. Chopping wood
B. Silver tarnishing (changing color)
C. Grape kool-aid mix dissolving in water
D. Dry ice turning into a gas (sublimation- a change of state)
B. silver tarnishing
C= ( F - 32) / 1.8
86 F = ?
Answer:
C = 30
Explanation:
C = (86 - 32)/1.8
C = (54)/1.8
C = 30
It takes 120 mL of 0.15 M of carbonic acid (H2CO3) to neutralize 300 mL of sodium hydroxide (NaOH) for the following balanced chemical reaction:
2NaOH + H2CO3 → N2CO3 + 2NaOH
The concentration of the sodium hydroxide _____.
how do you Calculate the molarity of 250 ml of solution in which 2.7 g of MgCl2 are dissolved
Answer:
Molar mass of MgCl2 is 95 g/mol
Mg = 24 g/mol and Cl = 35.5 ×2 = 71 g/mol
moles = mass given/ molar mass
= 2.7/95 = 0.028 mol
volume = 250/1000 = 0.25 dm3 (ml is the same as dm3)
molarity of MgCl2 = moles/volume
= 0.028/0.25
= 0.112 mol/dm3
patient requires blood transfusion. what is the next thing to do? discuss
Which of the following is not part of an amino acid?
A. ammonium group
B. carboxylate group
C. ether group
D. unique "R" group
Answer:
C
Explanation:
Ether group does not exist in amino acids
Ammonium group is on one side
the carboxylate group is opposite to the ammonium group
the R group defines what amino acid it is.
As an electron in an atom moves from a higher energy state to a lower energy state, the atom
A
becomes a negative ion
В.
becomes a positive ion
С.
releases energy
D.
absorbs energy
Answer:B
Explanation:
What is the mass of an aluminum block if the density of aluminum is 2.70
g/cm and the volume of that block is 4.8 cm?
Answer: 50 M
Explanation:
Mass
Density×Volume2.7(4.8)11.6111.6gFormula used
Density=Mass/VolumePolyvalent ions are
1) Anions with variable charges
2) Cations from columns 3 to 12
3) Ions that can be positive or negative
An aqueous solution was prepared by dissolving 266.07 g of AgNO3 ( 169.88 g/mol) in enough water to make a total volume of 250.0 ml. What is the molarity of the solution
Answer:
The correct answer is 6.265 M.
Explanation:
To find the molarity of the solution, we first must recall that molarity represents the number of moles of solute divided by the number of liters of solution. Thus, our first step should be to convert the solute amount in grams to moles, using the given molar mass.
266.07 g * (1 mol/169.88 g) = 1.5662 mol
Now, we can find the molarity using the following formula:
Molarity = moles solute/liters solution
M = 1.5662 mol/0.25 L
M = 6.265 M
Therefore, the molarity of the solution is 6.265 M.
Hope this helps!
Define Endothermic reaction in terms of Deta H
I didn't learn about that topic in school,but I found this :
I hope it helps<3
When the radiation isn't quite strong
enough to kill right away a terrible
Condition follows what is it called
and what is happening.
need help with question please ..
-20 points
Answer:
B oklolol
[tex][tex]\purple{\rule{45pt}{7pt}}\purple{\rule{45pt}{999999pt}}[tex][/tex]
which planet is closests to the moon
Answer:
Earth
Explanation:
Answer:
Earth
Explanation:
Hope this helps! Pls give brainliest! Also, please sub to Kgirl633 on yt.
Can someone help? Thank you.
that' the answer i don't need an explanation
Diazene, N2H2 (also known as diimine), is commonly used as a reagent for organic syntheses. Label each image with the type of
bond in diazene that it shows.
The first image shown at the left hand side is a pi bond. The other two images show sigma bonds.
In chemistry, a bond results from the overlap of atomic orbitals. This overlap may be end to end (sigma bond) or side by side (pi bond). Having said this, it is easier to decide whether the bonds in the image shown are sigma or bi bonds.
If we label the images; 1,2,3 from left to right, we can see that the overlap in image 1 is side by side. The electron density lies above and below the plane of the bond. This is a pi bond. In images 2 and 3, the overlap occurs in an end to end manner. This is a sigma bond.
Learn more: https://brainly.com/question/14018074
what is the chemistry of super glue
cyanoacrylate
When cyanoacrylate polymerizes, the cyanoacrylate sticks together on an atomic level, and it becomes solid. Super Glue solidifies in all the microscopic crevices of an object that it moved into when it was a liquid, and it can form chemical bonds with any anions in the object.
50 PTS!!!!!
What type of chemical reaction is Aerobic Cellular Respiration?
Answer: During aerobic respiration, catabolic reactions convert larger complex organic molecules into ATP, the chemical that drives most physiological processes in the body.
Explanation:
If 2.5 moles of PA react completely, how many
moles of P203 are formed?
Answer:
For every 2 moles of Na used, 2 moles of NaCl are produced.
Explanation:
calculate the mass percentage of each element in aluminum oxide.Then calculate themass of aluminum in a 3.62 gram sample of of aluminum
1. The mass percentage of each element in aluminum oxide Al₂O₃ are:
i. The mass percent of Al in Al₂O₃ is 52.9%
ii. The mass percent of O in Al₂O₃ is 47.1%
2. The mass of Al in 3.62 g of Al₂O₃ is 1.73 g
1i. Determination of the percentage of Al
Molar mass of Al₂O₃ = (2×27) + (3×16) = 102 g/mol Mass of Al of Al₂O₃ = 2 × 27 = 54 gPercentage of Al =?Percentage = mass / mass of sample × 100
Percentage of Al = (54 / 102) × 100
Percentage of Al = 52.9%
1ii. Determination of the percentage of O
Molar mass of Al₂O₃ = 102 g/mol Mass of O of Al₂O₃ = 3 × 16 = 48 gPercentage of O =?Percentage = mass / mass of sample × 100
Percentage of O = (48 / 102) × 100
Percentage of O = 47.1%
2. Determination of the mass of Al in 3.62 g of Al₂O₃.
102 g of Al₂O₃ contains 54 g of Al.
Therefore,
3.62 g of Al₂O₃ will contain = (3.62 × 54) / 102 = 1.73 g of Al.
Thus, 1.73 g of Al is present in 3.62 g of Al₂O₃.
Learn more about percentage composition: https://brainly.com/question/3940233
What is black powder made of? (Please provide percentage composition of elements as well) Will give brainliest
Answer:
Black powder has 3 main ingredients: Sulfur ([tex]S[/tex]), charcoal ([tex]C_{7}H_{4}O[/tex]), and potassium nitrate ([tex]KNO_{3}[/tex]).
Charcoal is basically just burnt wood and potassium nitrate can easily be displaced.
Keep in mind that this is BLACK POWDER and not actual gunpowder. The difference between the both is significant since gunpowder has a lot more refining processes it has to go through to be actually used in firearms and such.
The percentage composition of black powder should be 75% Potassium Nitrate, 10% Sulfur, and 15% charcoal.
Should be noted that black powder is not a safe compound to deal with, as static friction could ignite it.
There are other alternatives to Black powder such as nitroglycerin (used in dynamites) which is way more powerful and useful in doing mines and exploration but is an extremely tricky and reactive substance to work with.
I do hope this is just for educational purposes because you need to be certified to even just experiment with this (and there are laws to synthesize such as well, which I won't take any responsibility for)
Answer:
sulfur, charcoal and potassium nitrate
Explanation:
Payback
What is the total pressure exerted by a mixture containing two gases if the partial pressure of one gas is 70 kPa and the partial pressure of the other gas is 30 kPa?
Answer:
The total pressure of a mixture of gases can be defined as the sum of the pressures of each individual gas: Ptotal=P1+P2+… +Pn. + P n . The partial pressure of an individual gas is equal to the total pressure multiplied by the mole fraction of that gas.
Explanation:
hope this helps have a wonderfull day!
Which pair of elements form an ionic bond with
each other?
A. KCL
B. ICL
C. PCL
D. HCL
I think it’s A and D but if it’s not both can you please explain why it’s one and not the other?
Answer:
Yes Both A) KCL and D) HCL are correct...
Answer:
It's only A
Explanation:
Potassium (K) is a metal and Chlorine (Cl) is a nonmetal, and ionic compounds are formed between metals and nonmetals. So KCl forms ionic bonds.
Hydrogen (H) and Chlorine (Cl) are both nonmetals, and only covalent bonds form between nonmetals. (Only exception is when its an acid, then it's ionic)
Also, the question indicated which "pair" and not "pairs" meaning that there is only one answer, and I'm more likely to go with A rather than D.
1. List the ketose carbon(s) that is(are) reduced with NaBH4.
Answer:
ehh im nit sure but here!
Explanation:
Why does the Hubble Space Telescope take clearer pictures than other telescopes?
Answer:
Space-based telescopes like Hubble get a much clearer view of the universe than most of their ground-based counterparts. ... Ground-based telescopes can't do the same, because the Earth's atmosphere absorbs a lot of the infrared and ultraviolet light that passes through it.
Describe echolocation. Give an example of an animal that uses echolocation.
dolphin and whales use echolocation
Would you expect a Boron (B) atom with atomic mass = 9.999 to be stable?
The balance of forces allows to find the result for the question if the isotope of boron 9.99 una is stable:
The boron isotope of mass 9.99 uma is unstable because the repulsive force increases.The stability of atomic nuclei depends on the balance the force is electrostatic repulsion between the protons and the strong interaction of attraction.
One way to achieve this balance is to increase the separation of the protons with uncharged particles between them, the neutral ones, the strong interaction is of the same magnitude for protons and neutrons, therefore the repulsion is decreased and the strong attraction interaction is maintained. .
In the case of Boron, which has 5 protons, the stable structures have more atomistic 10 and 11 una, which is why it has 5 and 6 neutrons each. Therefore each proton has a neutrons next to it and in the other case a proton at the end has two neutrons, this causes the distance between the protons to increase, decreasing the electrostatic repulsion.
It indicates that we have a Boron nucleus of mass 9.999. The number of protons must remain fixed, therefore there are only 4 neutrons.
Consequently, some of the protons does not have a neutron next to it and can approach the other proton, therefore the electrostatic repulsion increases and the stability of the atom decreases.
In conclusion, using the balance of Forces we can find the result for the question if the isotope of boron 9.99 una is stable:
The boron isotope of mass 9.99 amu is unstable because the repulsive force increases.Learn more about nuclear stability here: https://brainly.com/question/897383
I NEED HELP WItH THIS 5th GRADE QUESTION ITS VERY VERY EASY no Links PLZ and I will Report any useless AWnser PLZ HELP WILL mARK AS BRAINLIST AND Will giVE 1000 Points if correct Answer
How is the mass of a solid measured?
By estimating
With a beaker
With a ruler
With a scale
Answer:
A Beaker or graduated cylinder
Explanation:
Place the solid into the graduated cylinder. Measure the amount of water in the graduated cylinder. The product is the solid's mass wich i mean by that is what number the water level is at.
Answer:
Beaker
Explanation:
Sulfuric acid reacts with sodium carbonate to form water, a salt, and a gas. Write the formulas for the salt and other compound that are formed in the reaction.
Answer:
H2So4 + Na2Co3 -> H20 + Na2So4 + CO2
The chemical formulas for the salt and other compound that are formed in the reaction are Na₂SO₄,H₂O and CO₂.
What is chemical formula?Chemical formula is a way of representing the number of atoms present in a compound or molecule.It is written with the help of symbols of elements. It also makes use of brackets and subscripts.
Subscripts are used to denote number of atoms of each element and brackets indicate presence of group of atoms. Chemical formula does not contain words. Chemical formula in the simplest form is called empirical formula.
It is not the same as structural formula and does not have any information regarding structure.It does not provide any information regarding structure of molecule as obtained in structural formula.
There are four types of chemical formula:
1)empirical formula
2) structural formula
3)condensed formula
4)molecular formula
Learn more about chemical formula,here:
https://brainly.com/question/29031056
#SPJ5