HELP!! 75 pts
A 12.00 gram sample of a crude ore contains 2.89 % HgS. What is the percentage of mercury in the ore? (2.49)
The percentage of mercury in the ore : 2.49%
Further explanationGiven
12 g of sample
2.89% HgS
Required
The percentage
Solution
mass of HgS in the ore :
= 2.89% x 12 g
= 0.3468 g HgS
Mass of Hg in HgS :
= (Ar Hg/MW HgS) x mass HgS
= (200.592/232,66 g/mol) x 0.3468
= 0.299 g
% mercury (Hg) in sample(a crude ore) :
= (0.299 g : 12 g) x 100%
= 2.49%
You have 50 L of CO2 gas at standard temperature and pressure (STP). What would need to be done to the pressure to cut the volume of gas in half?
The pressure is doubled(2 atm)
Further explanationGiven
50 L of CO₂ gas at STP
Required
The pressure
Solution
Changing pressure, constant temperature⇒Boyle's Law
At a fixed temperature, the gas volume is inversely proportional to the pressure applied
[tex]\tt \rm p_1V_1=p_2.V_2\\\\\dfrac{p_1}{p_2}=\dfrac{V_2}{V_1}[/tex]
STP⇒1 atm, T=273 K
The (new) volume of gas in half, so V₂=0.5 V₁ = 0.5 x 50 = 25 L
Because the gas volume is inversely proportional to the pressure than the pressure doubled = 2 atm
Or we can use the formula :
P₂=(P₁V₁)/V₂
P₂=(1 atm x 50 L)/25 L
P₂= 2 atm
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Science
My teacher gives me a block of some unknown material. I weigh it and find out that it weighs 22.5g. I then heat it up using 2067J of energy and notice that it only changes by 25 degrees celsius. What is its specific heat?
The specific heat of unknown material : 3.675 J/g °C
Further explanationGiven
mass of block = 22.5 g
Q = heat = 2067 J
Δt=25 °C
Required
The specific heat
Solution
Heat can be formulated :
Q = m.c.Δt
Input the value :
2067 J = 22.5 g x c x 25 °C
c = 3.675 J/g °C
96.0 g. of a gas occupies 48.0 L at 700.0 mm Hg and 20.0 °C. What is its molecular weight?
Answer:
I hope this helps 52.2 g/mol
Explanation:
1) Solve for the moles using PV = nRT:
n = PV / RT
n = [(700.0 mmHg / 760.0 mmHg atm¯1) (48.0 L)] / [(0.08206 L atm mol¯1 K¯1) (293.0 K)]
n = 1.8388 mol
2) Divide the grams given (96.0) by the moles just calculated above:
96.0 g / 1.8388 mol = 52.2 g/mol
Molecular weight of the gas is 52.2 g/mol.
What is ideal gas equation?Ideal gas equation is a hypothetical equation which tells about the behavior of the gas under standard condition and it ca be described as:
PV = nRT, where
P = pressure = 700.0 mm Hg (given)
V = volume = 48.0 L (given)
R = universal gas constant = 0.08206 L atm mol¯¹ K¯¹
T = temperature = 20.0 °C = 293 K
On putting theses values in the above equation we get for moles is as:
n = (700 × 48) / (0.08206 × 293) = 1.8 moles
We know that moles can be represented as:
n = W / M, where
W = given weight = 96g
M = molecular weight = to find?
Putting values in the mole equation, we get
M = 96 / 1.8 = 52.2 g/mol
Hence, molecular weight of gas is 52.2 g/mol.
To know more about ideal gas equation, visit the below link:
https://brainly.com/question/1056445
how is copper sulphate different to copper sulphide in terms of the elments it contains
Answer:
An Element is a substance made up of only one type of atom as like gold, copper, oxygen, etc.
Copper sulphate with molecular formula [tex](CuSO_4)[/tex], the elements are copper, sulphur and oxygen. It is formed by combination of [tex]Cu^{2+}[/tex] cation and [tex]SO_4^{2-}[/tex] anion.
Copper sulphide with molecular formula [tex](CuS)[/tex], the elements are copper and sulphur. It is formed by combination of [tex]Cu^{2+}[/tex] cation and [tex]S^{2-}[/tex] anion.
Look at the activity series and select which two of the following reactions
would happen on their own. (Remember, if the lone element is more active
than the metal in the compound, the lone element will react and replace the
metal in the compound.)
The Activity Series
Most Active
Lithium (Li)
Potassium (K)
Calcium (Ca)
Sodium (Na)
Aluminum (AI)
Zinc (Zn)
Iron (Fe)
Tin (Sn)
Lead (Pb)
(Hydrogen) (H)
Copper (Cu)
Silver (Ag)
Gold (Au)
Least Active
O A. 2Li + ZnBr2 + 2LiBr + Zn
B. 3Ca+ Al2O3 + 2Al + 3Cao
C. Al +3LICI - AlCl3 + 3Li
D. Sn + ZnSe → SnSe + Zn
Answer:
b
Explanation:
because the correct answer
*CHEMISTRY*
An atom was determined to have an electron configuration of 2-5. This atom should have a Lewis dot diagram with....
O 7 dots
O 5 dots
O 2 dots
O 1 dot
Determine the number of valence electrons for following (Ne) 3s2 3p4
a.3
b.2
c.4
d.7
e.16
f.6
Pls help
Answer:
F. 6
Explanation:
How many moles are in 0.532g Ca(OH)2?
Answer:
0.0072mole
Explanation:
Given parameters:
Mass of the compound given = 0.532g
Unknown:
Number of moles = ?
Solution:
To solve this problem, we need to use the expression below:
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of Ca(OH)₂ = 40 + 2(16 + 1) = 74g/mol
Number of moles = [tex]\frac{0.532}{74}[/tex] = 0.0072mole
urgent plzz help meeee thx
The balanced equation :
C₃H₈(g)+5O₂(g)→3CO₂(g)+4H₂O(g)
Further explanationGiven
The reaction of Propane(combustion)
Required
Balanced equation
Solution
Reaction
C₃H₈(g)+O₂(g)→CO₂(g)+H₂O(g)
Give a coefficient(the most complex compound = 1) :
C₃H₈(g)+aO₂(g)→bCO₂(g)+cH₂O(g)
Make an equation :
C, left = 3, right=b⇒b=3
H, left = 8, right=2c⇒2c=8⇒c=4
O, left = 2a, right=2b+c⇒2a=2b+c⇒2a=2.3+4⇒2a=10⇒a=5
The equation becomes :
C₃H₈(g)+5O₂(g)→3CO₂(g)+4H₂O(g)
Which of the following is included in the study of Geology?
a : the composition of the sun
b : the composition of air
c : the composition of water
d : the composition of the materials that make up the planet
10. How many moles of Ne are in a 0.50L tube at 200kPa and 50 °C? 11,60
Answer:
0.04 mol Ne
General Formulas and Concepts:
Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Gas Laws
Combined Gas Law: PV = nRT
P is pressure (in kPa)V is volume (in liters)n is amount of molesR is gas constant - [tex]\displaystyle 8.314 \frac{kPa \cdot L}{mol \cdot K}[/tex]T is temperature (in Kelvins)Explanation:
Step 1: Define
P = 200 kPa
V = 0.50 L
T = 50°C
Step 2: Identify Conversions
Temperature Conversion: K = °C + 273.15
Step 3: Convert
Substitute T [TC]: K = 50°C = 273.15Add: K = 323.15Step 4: Find Moles
Substitute [CBL]: [tex]\displaystyle (200 \ kPa)(0.50 \ L) = n(8.314 \frac{kPa \cdot L}{mol \cdot K} )(323.15 \ K)[/tex]Multiply: [tex]\displaystyle 100 \ kPa \cdot L = n(2686.67 \frac{kPa \cdot L}{mol})[/tex]Isolate n: [tex]\displaystyle 0.037221 \ mol = n_{Ne}[/tex]Rewrite: [tex]\displaystyle n_{Ne} = 0.037221 \ mol[/tex]Step 5: Check
Follow sig fig rules and round. We are given 1 sig figs as our lowest.
0.037221 mol Ne ≈ 0.04 mol Ne
I needa know the first one help✋
Answer: Soil permeability is the property of the soil to transmit water and air and is one of the most important qualities to consider for fish culture. A pond built in impermeable soil will lose little water through seepage. The more permeable the soil, the greater the seepage.
Explanation:
Which of the following is the correct formula for Ca2+ reacting with NO2??
O A. Ca NO2
O B. Ca(NO2)2
O C. Ca (NO)
O D. CaNO2
Answer:
B. Ca(NO2)2
Explanation:
Ions (charged atoms) combine with one another to form stable ionic compounds. In this case, calicium ion (Ca2+) is said to react with NO2, which has a charge of -1 i.e. +1-1(2) = 1-2 = -1.
This means that calcium has a charge of +2 while nitrite ion has charge of -1, hence, when they combine, they exchange their charges, which become their subscript as follows:
Ca2+ + NO2- → Ca(NO2)2
Ca(NO2)2 is a stable ionic compound called calcium nitrite. Notice that it takes two atoms of NO2- to react with one atom of Ca2+.
1. What are the characteristics of a solid? it has blank shape and a definite blank
Solids are defined by the following characteristics:
definite shape (rigid)
definite volume.
particles vibrate around fixed axes.
8. When rubidium and fluorine combine to produce the compound RbF, che ions
formed have the same electron configuration as atoms of
a neon, only
b both argon and neon
c both krypton and neon
d both xenon and neon
Answer:
The answer is C, both krypton and neon.
Explanation:
I got the answer wrong and my teacher told me that c is the right answer choice
Ions can be made by single element or covalently bonded group of elements. The covalently bonded group of elements is called polyatomic ions or polyatomic atoms. Therefore, the correct option is option C.
What is Ions?Any species that contain charge whether it is positive charge or negative charge is called ions. The example of polyatomic ions are sulfate, phosphate, nitrate etc.
Cation is the species that loose electron and attain positive charge while anion is a species which gain electron and attains negative charge so when anion and cation combine in fixed ration the the overall charge of the molecule is zero that is molecule is neutral, the charge over cation and anion is also called oxidation state.
Rb react as cation Rb ⁺ with electron distribution as [Kr] after removal of 1 electron from s orbital. F react as anion F⁻ with electron distribution [He] 2s² 2p⁶ which is equal to electronic configuration of neon.
Therefore, the correct option is option C.
To learn more about ions, here:
https://brainly.com/question/13692734
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What is the system of communication that involves an alphabet in which letters are represented by combinations of long and short
signals of light or sound?
A
Email
B)
Morse code
Binary code
D
Digital Signal Reception
Wireless intern
Answer:
B)
Morse code
Explanation:
Morse code is a communication system developed by Samuel Morse, an American inventor, in the late 1830s. The code uses a combination of short and long pulses – dots and dashes, respectively – that correspond to letters of the alphabet.
Answer:
b
Explanation:
I got it right on the exam. Morse code is your answer.
How does the Troposphere (atmosphere where weather takes place) affect the hydrosphere?
i need help with math
Answer: Atmosphere - Atmosphere - Troposphere: The lowest portion of the atmosphere is the troposphere, a layer where temperature generally decreases with height. This layer contains most of Earth’s clouds and is the location where weather primarily occurs. The lower levels of the troposphere are usually strongly influenced by Earth’s surface.
Explanation:
FOOD MACROMOLECULES INTRODUCTION
Biological Macromolecules
Most common elements in living things are carbon, hydrogen, nitrogen, and oxygen. These four elements constitute about 95% of your body weight. All compounds can be classified in two broad categories ---organic and inorganic compounds. Organic compounds are all based on carbon. Carbon can form single bonds with another atom and also bond to other carbon molecules forming double and triple bonds. This allows carbon based molecules to form single and double rings, chains, and branching chains. Most organic compounds are built primarily of carbon, hydrogen, and oxygen but in different ratios. Each small organic molecule can be a unit of a large organic molecule called a macromolecule. If the small organic units are identical or form patterns they are called monomers and the large organic molecule they form is called a polymer.
When monomers are joined together the reaction is called dehydration synthesis or condensation as water is produced when the monomers are bonded together. To break the polymers down again the reaction is called hydrolysis. Notice how water is used or produced in these two reactions shown to the right.
There are four classes of macromolecules: carbohydrates, lipids, proteins, and nucleic acids. Heterotrophs, like us, must get these biological macromolecules from our food which we break down into monomers through digestion. This makes the molecules small enough to cross cell membranes. Our cells use them either as energy sources or to build the carbohydrates, proteins, lipids, and nucleic acids that our body needs
Questions:
.
What atom makes up the backbone of biological macromolecules?
Answer:
this is nice..... cool
Explanation:
The reason that Noble Gases do not react is because
Answer:
Noble gases are odorless, colorless, nonflammable, and monotonic gases that have low chemical reactivity. The full valence electron shells of these atoms make noble gases extremely stable and unlikely to form chemical bonds because they have little tendency to gain or lose electrons.
Answer:
noble gas
Explanation:
noble gas don't react because they already fulfill the octet rule. and have 8 valence electron
Would anyone kindly tell me the answers or how to do this ♀️
Answer:
Its is not sodium- the answer to number 2 is CS+1 O-1 = CSO im not 100% sure but its something like that :)
Explanation:
Help me ! Which goes with which
Answer:
1. Cerium
2. Iodine
3. Potassium
4. Lead
5. Boron
6. Calcium
7. Krypton
8. Einsteinium
Explanation:
Hope it helped!
HELP DUE IN 5MIN WILL MARK BRAILIEST
pLS ANSWER THIS QUESTION THE QUESTION IN THE SCREEN SHOT HAVING TO DO WITH ICE AND WATER
Explanation:
The problem deals with a phase transition from solid to liquid. To the left we have ice and to the right we have liquid water.
For such change to take place, the process of melting must occur. During melting, a solid changes state from solid to liquid by taking energy from the environment.
In solid state, the molecules of the water are in a fixed state about their fixed lattice. As the solid ice gains energy from the environment, it begins to melt. Energy increase causes the molecules of the water to start flowing to form a liquid.what is the formula for trinitrogen pentafluoride?
Answer:
S2I3
I can't type it on the key board but it's S and 2 is small down side
I and the 3 is down side too
Who can help me with this? I will give brainliest lmk!
IN THIS ORDER: nucleon, neutrons, element, different, isotopes, industrial
hope this helps!
An atom of sodium can transfer its one valence electron to an atom of...
O magnesium to complete the octet rule
O fluorine to complete the octet rule
O nitrogen to complete the octet rule
O calcium to complete the octet rule
Answer:
I believe it is B,fluorine to complete the octet rule
Explanation:
Answer:
fluorine to complete the octet rule
Explanation:
A chemical equation is balanced by what
-Adding coefficients
-Changing the subscripts -erasing elements as necessary
-Adding elements as necessary
Answer:
adding coefficient
Explanation:
To balance a chemical equation we have to place coefficients as needed in front of the symbols or formulas so the same number of each type of atom occurs in both reactants and products
Which of these discoveries contradict components of Dalton’s atomic theory? Check all of the boxes that apply.
Atoms contain smaller particles: protons, neutrons, and electrons.
Atoms of a given element can bond to other atoms only in specific ways.
Atoms of a given element can have different numbers of neutrons.
Nuclear reactions can change an atom of one element into an atom of another element.
All atoms of a given element have the same number of protons.
Answer:
A, B, D
Explanation:
Ed22
HELP ME PLEASE!!!....
Answer:
That's Law of Motion because the second law is based on acceleration of an object and its mssd but the boat isn't accelerating.
The third law is based on if the object has an equal and opposite force but there's no opposite force compelling the action