P 1. Elements X and Y react to form an ionic compound a formula XY. What could be the proton (atomic) numbers of X and Y?
X | Y
A | 3 | 8
B | 6 | 8
C | 8 | 16
D | 12 | 16
Answer:
the answer is C
Explanation:
This is because group6 elements are diatomic and when they are chemically combined their subscript 2 cancels out
what has fewer organisms then a domain but it also has more organisms then a phylum
Answer:
a species
Explanation:
Help me in the 10 the number. Clue- helium and hydrogen make up the first of these
Answer:
helium and hydrogen make up the first of these
the answer is period
Can someone please explain the steps to the correct answers?
Explanation:
1. b is correct because 10^-2 is 1/100. multiplying that by 1.862 is 0.01862
2. 6 feet 10 inches = 82 inches. multiplying 82 by 2.54 we get 208.28. there are only two sig figs so it's 210 cm, not 0.21 cm.
3. 25.2 x 39370 = 992000, which is 9.92 x 10^5.
What would be the partial pressure of nitrogen, PN2, in a room in which the total air pressure was 0.987 atm?
This problem is providing describing a room in which air has a total pressure of 0.987 atm and the partial pressure of nitrogen is asked, turning out to be 0.746 atm.
In such a case, we can start by looking at the provided table, which shows the composition of dry air in mass basis, which means we must convert the composition of nitrogen to mole fraction by knowing that the average molar mass of air is 28.9647 g/mol, and thus, we infer that the mole fraction of nitrogen in air is about 0.755 according to:
[tex]x_{N_2}=\frac{0.781*14.0067g/mol*2}{28.9647g/mol} =0.755[/tex]
Then, we recall the Dalton's law version that relates total pressure, partial pressure and mole fraction written for nitrogen:
[tex]P_{N_2}=x_{N_2}P[/tex]
Finally, we plug in the previously calculated mole fraction and the total pressure of air to obtain:
[tex]P_{N_2}=0.755*0.987 atm\\\\P_{N_2}=0.746atm[/tex]
Learn more:
(Gas laws) https://brainly.com/question/8511562(Dalton's law) https://brainly.com/question/14119417In the conclusion to the snake mole lab, you have to convert 3.45 moles of (NH4)2S04 to
grams. What is the molar mass of (NH4)2504?
When a magnesium is heated, it burns in air with a dazzling white flame to form a white powder .What it called?
Balanced Equation –
[tex]\purple{\bf{2Mg + O_2 = 2MgO}}[/tex]
Physical states –
Magnesium → Mg ( In Solid State) Oxygen → [tex]\sf{O_2}[/tex] ( Gaseous State) Magnesium Oxide → MgO ( In Solid State Or White powder)_______________________________________
It is magnesium Oxide MgO2
Which dosage form is a semisolid preparation that contains very small solid particles that are suspended in a liquid
A GEL is a semisolid preparation that contains very small solid particles that are suspended in a liquid. A gel always contains an agent (e.g., agarose) that provides stiffness to the preparation.
A gel is a semisolid preparation that contains a gelling agent which provides stiffness to the preparation.
The gelling agent can be, for example, agarose (this gelling agent is used to prepare gels in electrophoresis).
In an agarose gel, agarose molecules are organized into three-dimensional (3D) structures similar to pores, which allow the passage of DNA fragments during electrophoresis.
Learn more about agarose gel here:
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100 POINTS PLEASE HELP
1. What is the molar mass of NaOH?
2.How many atoms are in 3.35 moles of Aluminum?
3.How many moles of CO2 gas are in a 101.25 L container filled with CO2 gas?
4.What is the mass of 13.7 moles of N2 gas?
5.How many moles are in 78.5 molecules of CaCO3?
Answer:
1) Molar mass of NaOH can be calculated by taking the atomic mass values in the periodic table. Na (Sodium) = 22.98g/mol, O (Oxygen) = 16g/mol, H (Hydrogen) = 1.01g/mol
Add all the the mass values together for NaOH's molar mass, so (22.98 + 16 + 1.01) = 39.99 or round it to 40g/mol
2) To find the atoms from the moles, you just multiply Avogadro's number (6.02 x 10^23) by the moles.
So 3.35 x (6.02 x 10^23) = 2.0167 x 10^24 atoms are in 3.35 moles of aluminum
3) If the question is asking under standard temperature and pressure, we know that if we divide the volume by the molar volume of a gas (which is 22.7 in standard temperature and pressure), we can get the moles.
So 101.25L / 22.7 = 4.46 mol
4) We know that to find the moles, it is the mass divided by the molar mass. If we rearrange the equation to solve for mass, we have to multiply the moles by the molar mass to get there.
Nitrogen's (N) molar mass on the periodic table is 14g/mol, but since Nitrogen is a diatomic element, it would be N2 by itself. So multiply 14 by 2, which will give you 28g/mol. N2's molar mass is 28g/mol.
Now you multiply 13.7 moles by 28g/mol, which will give you 383.6g
5) Now here I think you may have wrote the question wrong. Molecules would be at a way higher number than just 78.5, so I'm first just going to assume you meant 78.5g.
To get the moles from mass, you divide the mass of the compound by its molar mass. Molar mass of CaCO3 can be just calculated using the atomic mass values for each element in the compound (Ca is 40.07g/mol, C is 14g/mol, O3 would be 16 x 3 g/mol or just 48g/mol) and then adding them all together (40.07 + 14 + 48 = 102.07) which would give us 102.7g/mol.
Now, just divide the mass 78.5g by the molar mass 102.7g/mol
78.5/102.7 = 0.764 moles
Now on the offchance that you were actually referring to molecules, and you accidentally typed a different number doing this, you can find out the moles from the molecules by just dividing the number of molecules you have with avogadro's number (6.02 x 10^23)
So it would look something like this:
molecules of CaCO3 / 6.02 x 10^23
what is the molarity of a koh solution if 25.0 ml neutralizes 35.0 ml of a 0.200 m hcl solution?
If 25.0ml neutralizes 35.0 ml of a 0.200M HCl solution, the molarity of KOH solution is 0.28M
The reaction between KOH solution and HCl is written below.
[tex]HCl + KOH \rightarrow KCl + H_2O[/tex]
Volume of KOH, [tex]V_B[/tex] = 25.0 ml
Volume of HCl, [tex]V_A=35.0 ml[/tex]
Molarity of HCl, [tex]C_A=0.200 M[/tex]
Molarity of KOH, [tex]C_B=?[/tex]
Number of moles of HCl, [tex]n_A=1[/tex]
Number of moles of KOH, [tex]n_B=1[/tex]
The mathematical equation for neutralization reaction is:
[tex]\frac{C_AV_A}{C_BV_B} =\frac{n_A}{n_B}[/tex]
Substitute [tex]C_A=0.200 M[/tex], [tex]n_A=1[/tex], [tex]n_B=1[/tex], [tex]V_B[/tex] = 25.0 ml, and [tex]V_A=35.0 ml[/tex] into the equation above in order to solve for [tex]C_B[/tex]
[tex]\frac{0.2 \times 35}{C_B \times 25}=\frac{1}{1} \\\\25C_B=7\\\\C_B=\frac{7}{25} \\\\C_B=0.28M[/tex]
Therefore, the molarity of KOH solution is 0.28M
Learn more on molarity here: https://brainly.com/question/17138838
perform the converters
a) 32gr C2H4-in liters
b) 7,5 litera N2- in molecules
c) 1.4•10 ² ³ molecules CH4- in atoms
Answer:
the answers are given in the photo
What does it mean when the
frequency of a wave increases?
A. the amplitude increases
B. the amplitude decreases
C the wavelength becomes shorter
D. the wavelength becomes longer
Answer:
The answer is C
Can you put a brainliest for me
Explanation:
Answer:
the wavelength becomes shorter
Explanation:
frequency increases, the wavelength gets shorter. As the frequency decreases, the wavelength gets longer.
How many moles of CO2 are produced from 15.6 g of NaHCO3?
Answer:
0.185moles
Explanation:
1mole of bicarbonate produces 1mole of CO2
so 0.185 mole produces 0.185 moles of CO2
Determine the mass of O(2-) ions in 3 mol of alumina (Al2O3). Molar mass of O = 16)
Considering the rule of three and molar mass of O, the mass of O²⁻ ions in 3 mol of alumina Al₂O₃ is 96 grams.
By multiplying the number of moles by the subscripts next to each atom, you get the amount of each element present in the compound. IIf the same atom appears more than once in the compound, you must add its amounts.
So, in 1 mole of Al₂O₃, you have 2 ions of O²⁻.
Then you can apply the following rule of three: if 1 mole of the compound contains 2 ions of O²⁻, 3 moles of the compound contains how many ions of O²⁻?
[tex]amount of ions of O^{2-} =\frac{3 moles of Al_{2} O_{3} x2 ions of O^{2-}}{1mole of Al_{2} O_{3} }[/tex]
amount of ions of O²⁻= 6 ions
Being the molar mass of O 16 g/mole, this is the amount of mass that a substance contains in one mole, then the mass of O²⁻ can be calculated as:
6 x 16 g/mole= 96 grams
Finally, the mass of O²⁻ ions in 3 mol of alumina Al₂O₃ is 96 grams.
Learn more about molar mass:
https://brainly.com/question/3588290?referrer=searchResultshttps://brainly.com/question/25873251?referrer=searchResultsBoron and antimony are good elements to use as
Answer: Semiconductors
Explanation:
Please help !!!!!!!!
1) Write the equation for the reaction between the hydrocarbon and bromine using fully displayed formulae for the hydrocarbon and the organic product.
2) The reaction between methane and bromine gas in the presence of UV light also causes the bromine to lose color.
(a) Write an equation for this reaction
(b) This reaction is described as a substitution reaction. whereas the reaction between X and bromine is an addition reaction. Using the equations you have already written , explain the difference between addition and substitution
HELP ME PZLMSMS
E
D
D
F
F
Answer:
10.C
11.B
15.A
Explanation:
Which substances will make a salt when combined?
Vinegar and tea
Soda and wine
Soda and ammonia
Fertilizer and detergent
Answer:
Soda and wine is the answer to your question.
Explanation:
yo make salt you need a base and an acid. in this case the base is soda and the wine is acid. hope that helps :)
What is the atomic mass of an element that has 37 protons, 43 neutrons, and 36 electrons?
Answer:
the atomic mass of the element with 37 protons,43 neutrons and 36 electrons is 80
rank the crystal lattice structures in order of decreasing efficiency of space in the structure.
Rank the crystal lattice structures in order of decreasing efficiency of space in the structure.
1. Simple cubic
2. Body centered cubic
3. Face centered cubic
4. Hexegonal close packed
what soda was the first to use the two-liter bottle?
Answer:
Coca-Cola or Pepsi
Explanation:
Im sure one of those
why is it dangerous to wear contact lenses in the lab
Answer:
It is strongly recommended that students do NOT wear contacts lenses in the laboratory. Chemical vapors may penetrate the contact lens material and cause the lens to adhere to one's eye, which could be detrimental to the eye. Goggles are not vapor tight and do not completely eliminate this absorption.
what is a “ medium” in regards to waves ?
what is the equilibrium concentration of co at 1000 k?
Answer: For the reaction, K c = 255 at 1000 K. If a reaction mixture initially contains a CO concentration of 0.1550 M and a Cl 2 concentration of 0.171 M at 1000 K. 1.
Explanation:
I will give thanks, profile thanks, brainliest and 5 star
Answer: E.) C2N2H8
Explanation:
Answer:
E ) C2N2H8
Explanation:
Claim-Evidence-Reasoning
Question: Does the diagramed chemical equation above obey the Law of
Conservation of Matter?
Answer:
matter cannot be created or destroyed in chemical reactions. This is the law of conservation of mass. In every chemical reaction, the same mass of matter must end up in the products as started in the reactants. Balanced chemical equations show that mass is conserved in chemical reactions.
Explanation:
In an investigation that uses the scientific method, which step immediately follows making a hypothesis?
summarizing the results
asking a question
making observations
designing an experiment
C????
Answer:
The answer is designing an experiment
Explanation:
Since we already have a hypothesis, we need to test the hypothesis and this is done by designing an experiment that will do this test.
a chemical reaction in which bonds are broken is usually associated with
the release of energy
Which of the following best describes a balanced reaction?
A) A reaction that has the sam number and type of atoms on each side of the equation
B) A reaction that has the same number of atoms on each side of the equation
C) A reaction that has the and type of atoms on each side of the equation
D) A reaction that has the same number of molecules on each side of the equation
Answer:
A reaction that has the same number and type of atoms on each side of the equation
Explanation:
A pex
the photo has the question; please help asap ! i’m giving brainliest—i also have more chemistry, honestly i’m about to post a whole bunch of questions
Answer:
The process is to divide the molecules by Avogadro's number (6.02 x 10^23) to get the moles. And since it's specified at STP (standard temperature and pressure) we know that the molar volume would be 22.4L. So we can just multiply the moles by the molar volume in order to get the volume of H2S.
(2.18 x 10^24) / (6.02 x 10^23) = 3.62 moles (rounded)
Now just multiply the moles by the molar volume of STP, 22.4.
3.62 x 22.4 = 81 Liters (rounded) of H2S