1. How many moles of Boron is 1.25 x 1023 atoms of Boron? *
O 0.208 mol B
0 7.53 x 1046 mol B
O 1.35 x 1025 mol B
0 4.82 mol B
Answer:
0.208 mol B
Explanation:
There are 6.02 × 10^23 atoms in one mole of a substance, according to Avagadro's law.
According to this question, there are 1.25 x 10^23 atoms of Boron. This means that the number of moles in the Boron atom can be calculated thus:
number of moles (n) = number of boron atoms (nA) ÷ Avagadro's number
n = 1.25 x 10^23 ÷ 6.02 × 10^23
n = 0.2076 × 10^(23-23)
n = 0.208 × 10^0
n = 0.208 × 1
n = 0.208 moles of Boron
What is a poverty line?
what are the steps to naming simple ionic compounds
Answer:
To name an ionic compound, you simply need to find the names of the cation and anion present in the compound and make sure to revise the ends of metal names as needed. First, write out the name of the metal, followed by the name of the non-metal with its new ending.
Explanation:
Write the name of the cation, and then write the name of the anion, changing the ending to "-ide" if it's a single element and leaving it as it is if it's a polyatomic ion.
What happens at a constant temperature, as time progresses?
Answers -
1.Phase change
2.Bonding of particles
3.Separation of particles
4.The substance remains in its initial phase
PLEASE HELPP! EXPLAIN UR ANSWER AND ILL GIVE BRAINLIEST
Answer:
false it removes carbon dioxide ......The heart pumps blood to all parts of the body. Blood provides oxygen and nutrients to the body and removes carbon dioxide and wastes. As blood travels through the body, oxygen is used up,
Explanation:
Oxygenated blood travels from the lungs through the pulmonary veins and into the left side of the heart, which pumps the blood to the rest of the body (see Function of the Heart). ... Then the blood is pumped through the pulmonary artery to the lungs, where it picks up oxygen and releases carbon dioxide.
Answer:
true because your heart contains blood that flows through you body system
2) If you
move 50 meters in 10 seconds, what is your velocity?
Answer:
5 meter/second.
Explanation:
You dived the seconds, 10, by the meters, 50.
A regional metamorphic belt is divided into zones based upon
What is the mass of 0.55 mole
of magnesium chloride?
Answer:
SYMBOLS, FORMULAS AND MOLAR MASSES
OBJECTIVES
1. To correctly write and interpret chemical formulas
2. To calculate molecular weights from chemical formulas
3. To calculate moles from grams using chemical formulas
INTRODUCTION
Part I. Symbols and formulas
An element is a homogeneous pure substance made up of identical atoms. All matter is made
up of elements and, since chemistry is the study of matter, it is convenient to use symbols to represent
the elements rather than using the entire name.
By international agreement, specific symbols are assigned to each element (Note: This means
that while names of the elements vary with language, symbols are constant throughout the world.) Each
element is assigned a one- or two-letter symbol. The first letter is capitalized, the second (if there is
one) is not. While this often seems trivial, it is in fact a very important point. For example, in chemical
language Co represents cobalt, which is a metal and an element, while CO represents carbon monoxide,
a compound which is a colorless, odorless gas! Even when there is not an obvious correspondence,
for instance "MN", it can cause confusion. Do you mean the element manganese? Did you forget a
letter and mean something else? Are you using "M" to represent something else entirely? Chemists
sometimes use "M" to represent any metal. It is well worth the trouble to memorize the symbols for
common elements.
Since compounds consist of elements, the chemical formulas of compounds also consist of
elements with subscripts used to denote the number of atoms per molecule. If there is no subscript, it is
implied that there is one of that kind of atom. Ones never appear in chemical formulas. Not only do
subscripts denote ratios of atoms, they also denote the ratio of moles of element to one mole of
compound. Parentheses can be used to show groups of atoms, with the subscripts showing how many
groups there are. Parentheses are not used if there is only one group.
Examples: For one mole of the following compounds, how many moles of each element are
present?
MgCl2 1 mole Mg, 2 moles Cl
Mg(NO3)2 1 mole Mg, 2 moles N, 6 moles O
NaNO3 1 mole Na, 1 mole N, 3 mole O
AgCl 1 mole Ag, 1 mole ClPart II. Molar Masses
Each atom has a different size and therefore a different mass. The relative masses of each
element can be found on the periodic table. For example, one atom of magnesium weighs 24.31 amu
(atomic mass units). However, one mole of magnesium weighs 24.31 g. (Moles were planned that
way!) Since one mole of MgCl2 consists of one mole of magnesium and two moles of chlorine, the
mass of one mole of MgCl2 must be the sum of the masses of the elements. The mass of one mole of a
substance is called the molar mass or molecular weight.
Examples: What is the molar mass of the following compounds?
MgCl2 24.31 + 2(35.45) = 95.21 g/mol
Mg(NO3)2 24.31 + 2(14.01) + 6(16.00) = 148.33 g/mol
NaNO3 23.00 + 14.01 + 3(16.00) = 85.01 g/mol
AgCl 107.9 + 35.45 = 143.4 g/mol
(Note: Yes! You DO have to count significant figures when calculating molecular weight/molar
mass. However, the number of significant figures may vary depending on which periodic table you use.)
Chemists are generally interested in number of moles. Unfortunately, it is impossible to measure
moles directly. However, masses are easily measured, and if the chemical formula of the compound is
known, the molar mass can be used to determine the number of moles. The molar mass is defined as:
molar mass = grams/moles = g/mol (1)
Moles may be calculated by using molar mass as a conversion factor in dimensional analysis where
molar mass in grams = 1 (exactly) mole of compound (2)
This method is used in multi-step calculations. For example, if 0.873 g of MgCl2 is weighed out, it
is 9.17 x 10-3
moles.
1 mole
0.873g x 95.21 g = 9.17 x 10-3
mol MgCl2 (3)
However, 0.873 g of AgCl is only 6.09 x 10-3
mol.
1 mole
0.873g x 143.4 g = 6.09 x 10-3
mol AgCl (4)Molar mass may also be used to relate moles to grams. For example, 0.158 mol of MgCl2 is 15.2 g.
0.158 mol x 95.21 g = 15.2 g MgCl2 (5)
1 mol
Percent is used to express parts per one hundred. Usually in chemistry, it refers to
g of species of interest x 100 = % (6)
g of whole thing
Example: For the % Mg in MgCl2: In one mole of MgCl2, there are 24.31 g of Mg (molar mass of Mg,
the part we are interested in) and 95.21 g of MgCl2 (the whole thing), so %Mg in MgCl2 is
(24.31/95.21) x 100 = 25.53% Mg (7)
PROCEDURE
Work individually.
The formula for calcium phosphate is Ca3(PO4)2. Weigh about 2 g of calcium phosphate to the
nearest 0.001 g. In other words, you do not have to have exactly 2.000g, but you must know the
weight you have exactly. Acceptable results include but are not limited to: 1.985g , 2.035g, 2.314g
etc.
Be sure to report all results with the correct number of significant figures and appropriate units!
How many elements does 2H2O2 have?
Answer:
If the 2nd and third 2 are underscored then there are two hydrogen atoms and 1 oxygen atom
Explanation:
which cycle results in death of the host cell
A.lytic cycle
B.lysogenic cycle
C.both
Answer:
A. lytic cycle is the correct answer
transfer of energy by electromagnetic -science question
A.conduction
B.convection
C.radiation
D.reflection
Answer:
B. convention
Explanation:
hope you get the right answer
Is my answer correct?? Please correct me
Thank you!
Answer:
you are right
Explanation:
Dylan is completing an experiment in science class. The teacher gave Dylan a raw egg that had the shell removed. The egg is surounded by a membrane. Dylan gently placed the egg into a solution. Below is a diagram of the concentration of water molecules in the egg and in the solution.
Based on the diagram, what will happen to the egg?
A.
It will shrink because water molecules will move out of the egg until all the water molecules are in the solution.
B.
It will swell because water molecules will move into the egg until the concentrations are equal.
C.
It will swell because water molecules will move into the egg until all the water molecules are inside the egg.
D.
It will shrink because water molecules will move out of the egg until the concentrations are equal. HELPPPPPPPPPPPPPPPPPP PLS
Answer: AA
Explanation:
6. An unknown compound is analyzed and found to consist of 49% carbon, 2.7
% hydrogen, and 48.2 % chlorine. If the molecular mass of the compound is 150,
what is the molecular formula of the compound?
Answer:
Molecular formula = C₆H₄Cl₂
Explanation:
Given data:
Percentage of hydrogen = 2.7%
Percentage of carbon = 49%
Percentage of chlorine = 48.2%
Molar mass of compound = 150 g/mol
Molecular formula = ?
Solution:
Number of gram atoms of H = 2.7 / 1.01 = 2.67
Number of gram atoms of Cl = 48.2 / 16 = 1.36
Number of gram atoms of C = 49 / 12 = 4.08
Atomic ratio:
C : H : Cl
4.08/ 1.36 : 2.67/1.36 : 1.36/1.36
3 : 2 : 1
C : H : Cl = 3 : 2 : 1
Empirical formula is C₃H₂Cl.
Molecular formula:
Molecular formula = n (empirical formula)
n = molar mass of compound / empirical formula mass
Empirical formula mass = 12×3 + 1.01 ×2 + 35.5 = 73.52 g/mol
n = 150 / 73.52
n = 2
Molecular formula = n (empirical formula)
Molecular formula = 2 (C₃H₂Cl)
Molecular formula = C₆H₄Cl₂
a letter stating three things that need urgent fixing in your school
Answer and Explanation:
Computers ( The computers are very old and very slow, and we have to notice that almost everyone are using computers at the same time at the school, which makes it even harder for it to load up assignments. )The Rick Rolling ( Everyone keeps sending links to teachers and students saying that it is part of some assignment but then you have to listen to Rick Astley, they should really block these links. )The lockers ( The lockers are also very old and they are breaking down and rusting a lot from the moisture in the hallways. One of the lockers even broke down today!!! I hope they can fix this so no one else gets hit with a locker door. )Hope this helps! ;)
What would be the mass of 3 moles of water molecules?
a
54 grams
b 40 grams
C
30 grams
d 20 grams
Answer:
[tex]\boxed {\boxed {\sf A. \ 54 \ grams }}[/tex]
Explanation:
To convert from moles to grams, we must use the molar mass.
Recall that water's molecular formula is H₂O. It contains hydrogen and oxygen. Look up the two elements masses on the Periodic Table.
Hydrogen (H): 1.008 g/mol Oxygen (O): 15.999 g/molNow, use these masses to find water's mass. The subscript of 2 tells us there are 2 atoms of hydrogen, so we multiply hydrogen's mass by 2 and add oxygen's.
H₂O= 2(1.008 g/mol) + 15.999 g/mol = 18.015 g/molUse the molar mass as a ratio.
[tex]\frac{18.015 \ g \ H_2 O}{ 1 \ mol \ H_2 O}[/tex]
Multiply by the given number of moles.
[tex]3 \ mol \ H_2O*\frac{18.015 \ g \ H_2 O}{ 1 \ mol \ H_2 O}[/tex]
The moles of water will cancel.
[tex]3 *\frac{18.015 \ g \ H_2 O}{ 1 }[/tex]
[tex]3 *{18.015 \ g \ H_2 O}[/tex]
[tex]54.045 \ g \ H_2O[/tex]
Round to the nearest whole number. The 0 in the tenth place tells us to leave the number as is.
[tex]54 \ g \ H_2O[/tex]
There are about 54 grams of water in 3 moles.
Answer:
54 grams
Explanation:
First step is to find what one mole of water is in grams.
Water is H2O so that means we have two moles of Hydrogen.
H - 2 grams (on periodic table)
We have one mole of Oxygen.
O - 16 grams (on periodic table)
Add 2 and 16 to get 18 total grams in one molecule of H2O
Now multiply 3 times 18 to know how many grams in 3 moles of H2O
You end with
3x18=54 grams
Which of the following statements does not describe a physical property of chlorine?
O The color of chlorine gas is green.
O The density of chlorine gas at standard temperature and pressure is 3.17 g/L. OChlorine combines with sodium to form table salt.
O The freezing point of chlorine is -101°C.
Answer:
the chlorine gas is green
Explanation:
the density of
Therefore, the first option A is correct.
Learn more at :https://brainly.com/question/18327661?referrer=searchResults
Pls help!!!
Briefly describe how plasma TVs display colour.
How many moles of Na2SO4 are present in 426.12 grams of Na2SO4? (5 points)
Group of answer choices
2
3
5
6
Answer: It’s 2.9 moles
Explanation:
Answer:
b) 3
Explanation:
i got it right
Consider the reaction and the rate law below.
2O3 → 302
R= k[03]2
What is the overall order of the reactants in this rate law?
A. 0
B. 1
C. 2
D. 3
The overall order of the reactants in this rate law : 2
Further explanationGiven
Reaction
2O3 → 302
The rate law :
R= k[03]²
Required
The overall order
Solution
The overall order : the sum of orders for each reactant
For A + B ---> C + D
r = k [A]ᵃ[B]ᵇ
The overall reaction order is m+n
So for the rate law of R= k[03]², the overall order = 2
Which compound below has the highest iron content?
Feo
FeCl2
FeSO4
Fe(OH)2
ANSWER:
Fe(OH)2
Explanation:
Fe(OH)2
The highest iron content.
A compound is a substance that consists of the atoms or the ions of the two or more different elements that are joined by a chemical bond and can't be separated by any physical means. Like water is a compound of oxygen and hydrogen.
This the answer is Fe(OH)2.
The highest iron content of the iron is the second iron hydroxide, and it is an inorganic compound that makes salts from a compound of iron sulfate. Has white sold traces of oxygen which gives it a greenish tint. It can be seen in its mineralogical forms as a form of green rusting.Hence the option D is correct.
Learn more about the compound below.
brainly.com/question/22282338.
What is the mass of 14.4 moles Fluorine?
0.379g
274.8
1.32 g
2.64g
547 g
Answer:
D
Explanation: d
Answer:
547g
Hope i could help ;)
Please help!!! How many moles are in 4.87x1024 atoms of Mg
I 3. How many moles of H, gas are made when 3.2 x 1023 molecules of HCl are used? 2A1 + 6HCI ----> 2AlCl3 + 3H2
Answer:
0.265 moles
Explanation:
From the equation given;
Number of moles of HCl is 6 while number of moles of H is 3.
Now, we know from avogadro's number that 1 mole of a gas = 6.022 × 10^(23) molecules.
We want to find the number of moles of Hydrogen gas made when 3.2 x 10^(23) molecules of HCl are used.
Thus, converting this to moles gives;
(3.2 × 10^(23))/(6.022 × 10^(23)) = 0.53 moles
Thus, we can find the number of hydrogen gas by proportion as;
n = 3/6 × 0.53
n = 0.265 moles
Write Lewis dot structures for each of the following molecules. Use VSEPR to determine the shape of each molecule. Use electronegativity values to determine the polarity of each molecule.
PH3
CHCl3
H2CO
XeCl4
PBr5
TeF4
ICl5
BF3
KrF2
SO3
my question is butterfly emerges
Consider the rate law below.
R=k[A]2
What effect does doubling the concentration have on the rate?
A. doubles the rate
B. triples the rate
C. quadruples the rate
D. no effect on the rate
C. quadruples the rate
Further explanationGiven
The rate law :
R=k[A]²
Required
The rate
Solution
There are several factors that influence reaction kinetics :
1. Concentration 2. Surface area 3. Temperature 4. Catalyst 5. Pressure 6. StirringThe rate is proportional to the concentration.
If the concentration increased, the reaction rate will increase
The reaction is second-order overall(The exponent is 2)
The concentration of A is doubled, the reaction rate will increase :
r = k[A]² ⇒ r= k[2A]²⇒r=4k[A]²
The reaction rate will quadruple.
Describe the difference between ionization energy and electron affinity in terms of atomic structure.
Answer:
Please refer below to the attached file
Hope it helps
Please mark me as the brainliest
Thank you
Based on what you have learned about currents, how do you think this mass of trash ends up in the Great Pacific Garbage Patch?
Looking at the map, what ideas do you have about why the trash is "trapped" in this location?
how many
moles are in 9.01 x 1023 molecules of water. answer should be rounded to three significant figures.
A. 1.50
B. 15.0
C. 0.150
D. None of the above
Answer:
A. 1.50
Explanation:
9.01 x 1023 molecules* 1 mol/ 6.022×1023 molecules= 1.49618067087 moles
Rounded would be 1.50
PLEASEEEE HELP I WILL GIVE 30 POINTS Cobalt
Calcium
Platinum
Phosphorus
Part II:
Look at a periodic table, and in the space below type the missing chemical or symbol. Then answer the question below.
Iron:
Co:
Na:
Tin:
P:
F:
Fe:
Magnesium:
Uranium:
Ca:
Carbon:
Lead:
Ag:
Zn:
Ni:
Part III:
You have found a new element with the atomic mass of 119. In a paragraph explain where you would put in on the periodic table and why you would put it there. What type of properties would this element have? What would you call it?
Answer:
Iron: Fe
Co: Cobalt
Na: Sodium
Tin: Sn
P: Phosphorus
F: Flourine
Fe: Iron
Magnesium: Mg
Uranium: U
Ca: Calcium
Carbon: C
Lead: Pb
Ag: Silver
Zn: Zinc
Ni: Nickle
----------------
There is honestly no right answer for this but here is what I would put:
Atomic mass increases as you go from left to right. If you look at the periodic table, it would be between Sn and Sb. It would bet here because Sn is 118 and Sb is 121. Basing it off of Antimony and putting it in group 15, the properties are that it is metallic and is a poor conductor of heat. I would call it Stin, which would be shortened to St.