I really need an answer please help
Answer:
56g the time to convey he must take care of the full stops and then try to combine the two sentences that the time to convey
state mandeelev's periodic law explain mandeelev's periodic table with its limitation
Answer: Mendeleev's periodic law : The properties of element are a periodic function of the atomic masses . Limitations:-(1)positions of hydrogen is not correctly placed. (2) The positions of isotopes could not be explained . For ex:- cl35 are cl37 are placed in the same group.
Explanation:
The radius of an atom of gold (Au) is about . (a) Express this distance in nanometers (nm) and in picometers (pm). (b) How many gold atoms would have to be lined up to span 1.0 mm
Answer:
(a) 0.135 nm; 135 pm
(b) 3.70 × 10⁶ Au atoms
Explanation:
The radius of an atom of gold (Au) is about 1.35 A. (a) Express this distance in nanometers (nm) and in picometers (pm). (b) How many gold atoms would have to be lined up to span 1.0 mm.
(a)
Step 1: Convert the radius to meters
We will use the conversion factor 1 m = 10¹⁰ A.
1.35 A × 1 m/10¹⁰ A = 1.35 × 10⁻¹⁰ m
Step 2: Convert the radius from m to nm
We will use the conversion factor 1 m = 10⁹ nm.
1.35 × 10⁻¹⁰ m × 10⁹ nm/1 m = 0.135 nm
Step 3: Convert the radius from m to pm
We will use the conversion factor 1 m = 10¹² pm.
1.35 × 10⁻¹⁰ m × 10¹² pm/1 m = 135 pm
(b)
Step 1: Convert "1.0 mm" to meters
We will use the conversion factor 1 m = 10³ mm.
1.0 mm × 1 m/10³ mm = 1.0 × 10⁻³ m
Step 2: Calculate how many gold atoms would have to be lined up to span 1.0 × 10⁻³ m
We will divide 1.0 × 10⁻³ m by 2 times the radius (diameter) of an atom of gold.
1.0 × 10⁻³ m / (2 × 1.35 × 10⁻¹⁰ m) = 3.70 × 10⁶
which is of the following is not a cation
Answer:Option (b) is the correct answer.
Explanation:
When a neutral element loses an electron then it acquires a positive charge and it is known as a cation.
For example, when a neutral iron atom loses three electrons then it forms a ion.
On the other hand, when a neutral element gains an electron then it acquires a negative charge and it is known as a anion.
For example, a sulfate ion means ion.
Thus, we can conclude that out of the given options sulfate is not a cation.
Explanation:
Identify each described physical separation technique.
A. A solid mixture is heated. One component transitions directly between solid and gas.
B. A liquid is carefully poured out, leaving the solid behind in the container.
C. A solvent is added to dissolve only one mixture component and then the liquids are separated.
D. A solid is caught on paper or a membrane while the liquid passes through.
Answer:
A. A solid mixture is heated. One component transitions directly between solid and gas ---> Sublimation
B. A liquid is carefully poured out, leaving the solid behind in the container ----> Decantation
C. A solvent is added to dissolve only one mixture component and then the liquids are separated ----> solvent extraction
D. A solid is caught on paper or a membrane while the liquid passes through ---> Filtration using filter paper
Explanation:
A. Sublimation is a process of separating solids which sublimes (solids turning directly to gases) from a a mixture of other solids which do not sublime. When the mixture is heated, the solids which sublime are separated and those which do not are left behind. examples of solids which sublime are naphthalene, Iodine crystals, etc.
B. Decantation is the process of carefully pouring out a liquid from a mixture of it with a solid, leaving the solid behind. Example, a mixture of sand and water where water can be easily decanted, leaving the sand behind.
C. In the process of solvent extraction, a mixture of solids which are soluble in different solvent, one of the components is dissolved in a solvent in which it is soluble while the others are not. The solution is then filtered out and the solid is then separated from the solvent by evaporation.
D. In filtration using a filter paper, the solid-liquid mixture is passed through a filter paper which has pores the size through which liquids can pass through but the solid can not. therefore, the solid remains behind on the paper while the liquid passes through.
A is sublimation, B is decantation, C is solvent extraction, and D is filtration.
Separation of mixturesChemical mixtures are separated in different ways.
A mixture in which one of the components can sublime may be separated using sublimation. The sublime-able component transition from solid straight into gas.A mixture of a liquid plus solid can be decanted if the solid is allowed to settle below the liquid. The liquid can then be decanted off.Solvent extraction has to do with the recovery of a component of a liquid mixture. A solvent is poured into the mixture and the component to be recovered dissolves in the solvent. The liquid is then separated.Filtration is used to separate a mixture consisting of soluble and insoluble components. The insoluble component can be filtered off using a filter paper of suitable pore size.More on separation of mixtures can be found here: https://brainly.com/question/863988
A car is traveling at 8km per hour for 3 hours. What is the distance? 33 km 22 km 24 km 30 km
Answer:24
Explanation:
Sodium Phosphate reacts with calcium nitrate according to the following equation:
2 Na3PO4 + 3 Ca(NO3)2 - Ca3(PO4), + 6 NaNO3
-
If 49.33 grams of sodium phosphate reacts, how many grams of Calcium Phosphate is
produced?
Answer:
Mass = 46.52 g
Explanation:
Given data:
Mass of sodium phosphate react = 49.33 g
Mass of calcium phosphate produced = ?
Solution:
Chemical equation:
2Na₃PO₄ + 3Ca(NO₃)₂ → Ca₃(PO₄)₂ + 6NaNO₃
Number of moles of Na₃PO₄:
Number of moles = mass/molar mass
Number of moles = 49.33 g/ 163.94 g/mol
Number of moles = 0.300 mol
now we will compare the moles of Na₃PO₄ and Ca₃(PO₄)₂
Na₃PO₄ : Ca₃(PO₄)₂
2 : 1
0.300 : 1/2×0.300 = 0.15
Mass of Ca₃(PO₄)₂:
Mass = number of moles × molar mass
Mass = 0.15 mol × 310.14 g/mol
Mass = 46.52 g
What is the mass number for an atom of zinc containing 30 protons and 34 neutrons?
Answer:
64
Explanation:
mass number =proton + neutron
=30+34=64
A student dissolves 19.g of sucrose C12H22O11 in 425.mL of a solvent with a density of 0.82/gmL. The student notices that the volume of the solvent does not change when the sucrose dissolves in it. Calculate the molarity and molality of the student's solution. Round both of your answers to 2 significant digits.
Answer:
0.13M and 0.16m.
Explanation:
Molarity is defined as the moles of solute present in 1L of solution.
Molality is the moles of solute per kg of solvent.
To solve this problem we need to convert the mass of sucrose to moles using its molar mass and finding the volume in L of the solution and the mass in kg of solvent:
Moles sucrose:
Molar mass:
12C = 12*12.01g/mol = 144.12g/mol
22H = 22*1.005g/mol = 22.11g/mol
11O = 11*16g/mol = 176g/mol
Molar mass of sucrose is 144.12g/mol + 22.11g/mol + 176g/mol = 342.23g/mol
Moles are:
19.0g * (1mol / 342.23g/mol) = 0.0555 moles of sucrose
Liters solution:
425mL * (1L / 1000mL) = 0.425L
kg solvent:
425mL * (0.82g/mol) = 348.5g * (1kg / 1000g) = 0.3485kg
Molarity:
0.0555 moles / 0.425L
0.13MMolality:
0.0555 moles / 0.3485kg
0.16mSomeone help me with these questions 15 and 16. You can do 17 if you’d like
Answer:
For question 15, we use cloths, heat-resistant gloves. (From what I know, I am just a 7th grader. Forgive me.)
For question 16, we use bowls to drink soup, metal cans which we use to drink soda from, we use lunch boxes which are insulated or thermos can be used for bringing to school to eat lunch and keeping food warm, we use aluminium foil containers to keep food warm.
For question 17, I think it's related to chart above question 15 and etc, if it isn't then I don't think I may be able to help.
A mixture of Mg and Zn with a combined mass of 1.0875 g was burned in oxygen producing MgO and ZnO with a combined mass of 1.4090 g. How many grams of zinc was in original mixture
Answer:
0.9537g is the original mass of Zn in the mixture
Explanation:
We can solve this question using the molar mass of each compound involved:
Mg = 24.305g/mol
MgO = 40.304g/mol
Zn = 65.38g/mol
ZnO = 81.38g/mol
Mg-Zn:
1.0875g = 24.305X + 65.38Y (1)
Where X are moles of Mg and Y moles of Zn
MgO-ZnO:
1.4090g = 40.304X + 81.38Y (2)
(1.4090g - 81.38Y) / 40.304 = X
0.03496 - 2.0192Y = X
Replacing (2) in (1)
1.0875g = 24.305(0.03496 - 2.0192Y) + 65.38Y
1.0875 = 0.8497 - 49.077Y + 65.38Y
0.2378 = 16.303Y
0.01459 moles of Zn = Y
And the mass is:
0.01459 moles of Zn * (65.38g/mol) =
0.9537g is the original mass of Zn in the mixture
3. How many moles of HCl are present in 3.70 L of a 2.33 M HCl solution?
a. 0.63 mol
c. 1.58 mol
b. 0.28 mol
d. 8.6 mol
Answer:
8.6 mol
Explanation:
number of moles = molar concentration x volume in litre
number of moles = 2.33 M x 3.70 L = 8.6 mol
Question 4 of 10
Which of the following describes a chemical reaction?
A. Atoms in substances react with each other.
B. Molecules interact without bonds breaking.
C. Substances change shape but not properties.
D. Molecules mix without interacting.
SIR
Answer:
B.
Explanation:
Because one or more substances,the reactants are converted into one or more Different substances,the products. Hope this helps
What two “groups” are contained in every amino acid?
7.
How many grams are contained in 3.9 x 1023 sulfur atoms?
atoms → moles
grams
I
Answer: 20.775 g S
Explanation: 3.9x10^23 atoms = 0.648 mol
Atomic mass S = 32.08
S in grams = 20.775
draw the resonance structure of the three possible carbocation intermediate to show how methoxyl (-OCH3) diects bromination toward ortho and para position
Answer:
See explanation and image attached
Explanation:
We know that some substituted benzene reacts faster than benzene towards electrophillic substitution. This is often due to the activation of the benzene ring towards electrophillic substitution by resonance.
-OCH3 directs an incoming electrophile (such as during bromination) to the ortho or para position. This is made possible by resonance (mesomeric) effect as shown in the image attached to this answer.
Image credit: pinterest
8. In a blast furnace, iron (III) oxide is used to produce iron by the following (unbalanced) reaction:
Fe2O3 (s) + CO (g) -----> Fe (s) + CO2 (g)
If 4.00 kg Fe2O3 is available to react, how many moles of CO are needed?
How many moles of each product are formed?
Answer:
6
Explanation:
How many molecules of H2O are in 8.54 moles of H2O?
hurry !!!!
Answer:
5.14 * 10^24 molecules H2O
Explanation:
8.54 moles of H2O contains 8.54 x 6.022 x 10^23 = 5.14 x 10^24 molecules of H2O.
A drawing.Short description, A drawing.,Long description,
The drawing shows a wave of water moving to the right in a container. As the wave moves, the distance between the peak and trough of the wave gets shorter, but the distance between the peaks of the waves remains the same.
Question
What does the drawing show about the energy of the wave as it moves?
Answer options with 4 options
A.
The energy of the wave increases as shown by the increasing frequency.
B.
The energy of the wave decreases as shown by the decreasing amplitude.
C.
The energy of the wave remains the same as shown by the same wavelength.
D.
The energy of the wave regularly increases and decreases as shown by the peaks and troughs.
the picture is this:
Answer:
wow 15 points is alot
Explanation:
Identify the most common reaction conditions for the dehydration of 2,3-dimethyl-2-pentanol. A line-angle structure of 2,3-dimethyl-2-pentanol shows a chain of the following sequence:
a. A line terminus, a segment of three vertices, and a line terminus.
b. A CH3 group is attached to the first (from left to right) and the second vertices.
c. An OH group is attached to the first vertex.
Answer:
1) Acid
2) heat
Explanation:
Dehydration is a type of chemical reaction in which water is removed from an alkanol to yield one or more alkenes.
The reaction normally commences with a protonation of the -OH group by a proton from the acid. Water is always a good leaving group so it quickly departs creating a carbocation. The removal of a proton yields the alkene.
The major product is the one in which there is greater substitution around the C=C double bond.
The passenger airship Hindenberg exploded in 1937 while attempting to dock in New Jersey. Its 16 hydrogen filled cells were filled with a total of 200,000 cubic meters of hydrogen gas. Given a density of 0.0824 grams per liter, how many kilograms of hydrogen gas was used to fill the airship?
Answer:
16480 Kg
Explanation:
From the question given above, the following data were obtained:
Volume of Hydrogen = 200000 m³
Density of Hydrogen = 0.0824 g/L
Mass of Hydrogen (in Kg) =?
Next, we shall convert 200000 m³ to L. This can be obtained as follow:
1 m³ = 1000 L
Therefore,
200000 m³ = 200000 m³ × 1000 L / 1 m³
200000 m³ = 2×10⁸ L
Thus, 200000 m³ is equivalent to 2×10⁸ L.
Next, we shall determine the mass of Hydrogen. This can be obtained as follow:
Volume of Hydrogen = 2×10⁸ L
Density of Hydrogen = 0.0824 g/L
Mass of Hydrogen =?
Density = mass /volume
0.0824 = mass of Hydrogen / 2×10⁸
Cross multiply
Mass of Hydrogen = 0.0824 × 2×10⁸
Mass of Hydrogen = 16480000 g
Finally, we shall convert 16480000 g to kg in order to obtain the desired result. This can be obtained as follow:
1000 g = 1 kg
Therefore,
16480000 g = 16480000 g × 1 kg / 1000 g
16480000 g = 16480 Kg
Thus, the mass of Hydrogen used to fill the airship was 16480 Kg
PLEASE HELP:(((
What kind of reaction is used for electroplating?
O A. A nonspontaneous redox reaction
B. A spontaneous redox reaction
C. A precipitation reaction
D. A decomposition reaction
Explanation:
B.Electroplating involves passing an electric current through a solution called an electrolyte. A redox reaction is spontaneous if the standard electrode potential for the redox reaction is positive
HOCH2CH2OH(s) is classified as an
hope it's helpful
Explanation:
its is classified as ionic cyrstal
Explain how to create a Bohr model for the element carbon
Answer:
In order to create a Bohr model for carbon, you must start in the first shell of electrons. The first shell can hold up to 2 of carbons 6 electrons. After filling up the first shell you can move on to the second that can hold up to 8 electrons. The finished Bohr model would have 2 electrons in the first shell and 4 in the second shell.
Explanation:
Answer:
elemnt b
Explanation:
Which of these is true for the electrons of an atom? Choose
O have a positive charge
O found in the nucleus along with the protons
O found in the space surrounding the nucleus
O are attached to the positive charge of neutrons
What
Answer:
The 3rd one " C " because it surrounds the nucleus it's not known the inside
An electron is found in the space surrounding the nucleus.
What is an electron?An electron is a sub-atomic particle which is found in the extra-nuclear part of an atom. They are found revolving int the shells which surround the nucleus.It carries a negative charge of minus 1 .
They are the elementary particles as they do not have known components or structure. It has a mass which is approximately equal 1/1836 th that of proton.No two electrons can occupy the same quantum state according to the Pauli exclusion principle.
As all elementary particles, it too does possess both particle and wave characteristics. They can collide with each other and cause diffraction . Wave properties of electrons are easier to observe with aid of experiments, because of lower mass and longer de Broglie wavelength.
Learn more about electrons, here:
https://brainly.com/question/2845051
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How many grams of Li3N are produced when 4.7 X 10(23) atoms of lithium react?
Answer:
[tex]m_{Li_3N}=9.06gLi_3N[/tex]
Explanation:
Hello!
In this case, since the reaction between nitrogen and lithium to obtain lithium nitride is:
[tex]6Li+N_2\rightarrow 2Li_3N[/tex]
Starting by that amount of atoms of lithium, we first need to compute the moles of lithium via the Avogadro's number:
[tex]n_{Li}=4.7x10^{23}atoms*\frac{1molLi}{6.022x10^{23}atoms}=0.78molLi[/tex]
Now, by using the 6:2 mole ratio between lithium and lithium nitride and the molar mass of this product (34.83 g/mol), we can compute the required grams as shown below:
[tex]m_{Li_3N}=0.78molLi*\frac{2molLi_3N}{6molLi}*\frac{34.83gLi_3N}{1molLi_3N} \\\\m_{Li_3N}=9.06gLi_3N[/tex]
Best regards!
one number is three times of the other and their arithmetic mean is 10 find them
x = 10, y = 20/6
Further explanationGiven
one number is three times of the other
their arithmetic mean is 10
Required
The numbers
Solution
Suppose the numbers you are looking for are x and y, then :
x = 3y (equation 1)
The arithmetic mean : the average of values
(x+3y)/2=10
x+3y = 20 (equation 2)
Substitute equation 1 into equation 2
3y+3y=20
6y=20
y = 20/6
from equation 1 :
x= 3 x 20/6
x = 60/6
x = 10
In the explosion of a hydrogen-filled balloon, 0.10 g of hydrogen reacted with 0.80 g of oxygen to form how many grams of water vapor? (Water vapor is the only product.)
Express your answer using two significant figures.
Mass of water vapor produced : 0.90 g
Further explanationGiven
0.10 g of hydrogen reacted with 0.80 g of oxygen
Required
mass of water vapor produced
Solution
Reaction
2H₂ + O ⇒ 2H₂O
If we refer to the law of conservation of mass which states that the mass before and after the reaction is the same, then the mass of water vapor formed as a product is:
mass reactants = mass products
mass of Hydrogen + mass of Oxygen = mass of water vapor
0.1 g + 0.8 g = 0.90 g
Or we can also solve by using stochiometry (using the concept of moles) to find the mass of water vapor
How many ruthenium atoms can you line up across across the tip of a finger that is 3.6 cm in length. A ruthenium atom has an average atomic radius of 178 pm.
Answer:
1.0 × 10⁸ ruthenium atoms
Explanation:
Step 1: Calculate the diameter (d) of an atom of ruthenium
The diameter of an atom is twice its radius.
d = 2 × r = 2 x 178 pm = 356 pm
Step 2: Convert "d" to meters
We will use the conversion factor 1 m = 10¹² pm.
356 pm × 1 m/10¹² pm = 3.56 × 10⁻¹⁰ m
Step 3: Convert the distance of the tip of a finger (D) to meters
We will use the conversion factor 1 m = 10² cm.
3.6 cm × 1 m/10² cm = 0.036 m
Step 4: Calculate the number of atoms of ruthenium required
We will use the following expression.
D/d = 0.036 m/3.56 × 10⁻¹⁰ m = 1.0 × 10⁸
Which property is shared between liquids that are used in thermometers.
Answer:
the property that is shared between liquids us called thermometric property your welcome