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Which reactants could be used safely to prepare potassium chloride?
1. aqueous potassium hydroxide and dilute hydrochloric acid
4 answers
asked by
Marrion
1,958 views
If you propose an answer to a question that you will test to see whether it is true, which step of the scientific method are you
5 answers
asked by
help urself
1,039 views
A 0.4647-g sample of a compound known to contain only carbon, hydrogen, and oxygen was burned in oxygen to yield 0.8635 g of CO2
5 answers
asked by
shane
12,990 views
A concentrated weak acid is best described as which of the following?
(a) a solution with a high pH (b) a solution where the
5 answers
asked by
Lena
6,200 views
A 5.10-g sample of iron is heated from 36.0oC to 75.0oC. The amount of energy required is 89.54 J. The specific heat capacity of
5 answers
asked by
jann
4,907 views
Calculate ΔSfus and ΔSvap for HF.
Determine the entropy change when 7.60 mol of HF(l) freezes at atmospheric pressure. I
6 answers
asked by
Srah
20,644 views
a period 2 nonmetal, X, forms the molecular compound NX3. Which of the following are also correct formulas for molecular
4 answers
asked by
layla
2,301 views
Why are gamma rays generally not shown when writing nuclear equations ?
4 answers
asked by
TJ
1,111 views
What is the hybridization of the central atom in COH2??
Would the correct response, out of the following: a) sp b) sp^2 c) sp^3
5 answers
asked by
K
5,281 views
Mass percent is one way to represent solution concentrations, though not the only one. A common measure of solution
4 answers
asked by
Linda
761 views
A) a picture shows a container that is sealed at the top by a movable piston. Inside the container is a ideal gas at 1.00atm ,
10 answers
asked by
K
9,878 views
The mass of an evacuated 255-mL flask is 143.187g. The mass of the flask filled with 267 torr of an unknown gas at 25 degrees
6 answers
asked by
Steph
2,860 views
A 0.552 g sample of ascorbic acid(Vitamin C) was dissolved in water to a total volume of 20.0 ml and titrated with 0.1103 M KOH.
4 answers
asked by
Cooper
2,974 views
draw the lewis structure of CP. include ions pairs and charges.
4 answers
asked by
RQ
1,373 views
Air is approximately 80% nitrogen and 20% oxygen (on a mole basis). If 6 g of hydrogen is added to a 22.4 liter maintained at 0
1 answer
asked by
Jessica Lynn
853 views
a mixture of 10cm3 of methane and 10cm3 of enthane was sparked with an excess of oxygen. after coolin to room temp, the residual
4 answers
asked by
Pet
2,769 views
Which of the following reactions should be fast at room temperature? Which would be slow? Explain
A. KCl+AgNO3->KNO3+AgCl B.
6 answers
asked by
john
2,416 views
In a constant-pressure calorimeter, 60.0 mL of 0.340 M Ba(OH)2 was added to 60.0 mL of 0.680 M HCl. The reaction caused the
6 answers
asked by
Akle
702 views
The following data were collected for determining the concentration of suspended solids in a water sample. (D= 1.01 g/mL).
3 answers
asked by
James
1,426 views
A particular coal contains 2.55% sulfur by mass. When the coal is burned, it produces SO2 emissions which combine with rainwater
7 answers
asked by
DD
5,305 views
Help on part "c":
The forensic technician at a crime scene has just prepared a luminol stock solution by adding 19.0g of luminol
9 answers
asked by
K
25,426 views
For a molecule of fluorous acid, the atoms are arranged as HOFO.
What is the formal charge on each of the atoms? Enter the formal
7 answers
asked by
K
15,630 views
Rhodium has density of 12.41g/cc and crystallizes with the face-centered cubic unit cell.
Calculate the radius of a rhodium atom.
7 answers
asked by
K
2,183 views
Calcium nitrate will react with ammonium chloride at slightly elevated temperatures, as represented in the equation
Ca(NO3)2(s) +
4 answers
asked by
JAS
3,827 views
A 60.0 sample of water is heated to its boiling point. How much heat (in ) is required to vaporize it? (Assume a density of 1.00
4 answers
asked by
Anonymous
1,520 views
Calculate q when a system does 54 J of work and its energy is increased by 61 J??
I know the total change in energy of a system
3 answers
asked by
Sai
536 views
The decomposition of nitrogen dioxide 2NO2-->2NO+O2 occurs in a two-step sequence at elevated tempatures. the first step lis
3 answers
asked by
RAYRAY
2,008 views
The equilibrium constant for the reaction below is Kc = 9.1 10-6 at 298 K.
2 Fe3+(aq) + Hg22+(aq) 2 Fe2+(aq) + 2 Hg2+(aq)
3 answers
asked by
Amber
929 views
At constant pressure, which of these systems do work on the surroundings? Check all that apply.
2A (g) + B(s) --> 3C(g) 2A (g)
7 answers
asked by
Akle
14,966 views
A student used 10 mL water instead of 30 mL for extraction of salt from mixture. How may this change the percentage of NaCl
3 answers
asked by
Daisy
1,217 views
can you show me the formula for this problem.
calculate the grams of NaOH present in 9.0 ml of a 8.0 (m/v) NaOH solution. thank
5 answers
asked by
julia
6,681 views
What concentration of Cl– results when 993 mL of 0.521 M LiCl is mixed with 883 mL of 0.309 M MgCl2?
PLEASE HELP! I don't know
4 answers
asked by
DIANA
4,216 views
2H2+O2=2H2O
H=-484KJ Which answer best describes the transfer of heat that occurs when 1.41 mol of H2 reacts with 0.671 mol of
5 answers
asked by
lex
2,096 views
how do I work this question out?:
50.00g of NaCl are dissolved in water to give a solution that contains 2.500% NaCl by mass. The
1 answer
asked by
K
546 views
thank you VERY much for your replies, DrBob.
Another question, however: How many moles of ions -both cations and anions- are
1 answer
asked by
K
623 views
A gaseous hydrocarbon (an organic compound consisting of C & H) weighing 0.232g occupies a volume of 102mL at 23 degrees Celcius
1 answer
asked by
K
498 views
What is the exact method/formula used to calculate oxidation state #'s? & how does one know when to use the correct oxidation
1 answer
asked by
K
550 views
in addition to previous Q:
for eg: why is the oxidation state (#) of Ca in CaH2 "+2"? According to a p.table I have here +2 is
1 answer
asked by
K
571 views
what three hydrogen-containing polyatomic anions are essential components of living systems?
What does progesterone acetate do in
1 answer
asked by
Bryan
573 views
could someone please explain how to work out the highest fhydride and the highest flouride of ununhexium ,if the valance is 6
1 answer
asked by
jill
517 views
What forces hold iodine particles together???
Intermolecular forces called induced dipole-induced dipole attractions. I have also
1 answer
asked by
Jon
516 views
Why is iodine a different colour in different solutions?
Iodine in water is a dirty brown ikky color due to the polar water
1 answer
asked by
Jon
584 views
Calculate the molar solubility of gold(I) chloride (Ksp= 2.0 x 10^-13) in .10 M NaCN. The complex ion formed is [Au(CN)2]- with
1 answer
asked by
Kristina
1,227 views
What if I used the Ksp table how does that help? I really don't know
Devise a scheme for separating Al(NO3)3, AgNO3, Ca(NO3)2 and
1 answer
asked by
Mike
1,162 views
Molar mass of clacium hydroxide.
Isn't it 40.08 + 16.00 + 1.008???? Calcium hydroxide is Ca(OH)<sub>2</sub>. Therefore, the O and
1 answer
asked by
Jill
456 views
Convert 3.6 times 10 to the second atm to torr.
I don't understand how to get atm to torr???? 1 atm = 760 torr. Is the answer
3 answers
asked by
Jill
1,500 views
How do I work the following question? I found the amu of CaCO3=101.0872g/mol; 2HCL=72.92128g/mol;
2 answers
asked by
d
964 views
A 5.00 g sample of Al pellets (specific heat = .89 J/g degrees c) and a 10.00 g sample of Fe pellets (specific heat = .45 J/g
3 answers
asked by
Charlie
680 views
A 5.00 g sample of Al pellets (specific heat = .89 J/g degrees c) and a 10.00 g sample of Fe pellets (specific heat = .45 J/g
3 answers
asked by
Charlie
663 views
How would I go about answer this question?
If 72.26 g of hot water at 83.6 degrees C is mixed with 43.86 g of cooler wayer at
1 answer
asked by
Chung
380 views
Could you please look over my work and see if I did this correctly? Thanks
<b>When 3.200 g of liquid ethyl alcohol (C2H5OH) is
1 answer
asked by
Kate
477 views
Many home barbeques are fueled with propane gas C3H8.
What mass of carbon dioxide (in kg) is produced upon the complete
3 answers
asked by
K
2,816 views
I am still not quite grasping how to complete this problem:
Posted by K on Sunday, October 14, 2007 at 6:43pm. Many home
5 answers
asked by
K
629 views
For the reaction shown, find the limiting reactant for each of the following initial amounts of reactants.
4Al(s) + 3O2(g) ->
2 answers
asked by
K
906 views
A scientist wants to make a solution of tribasic sodium phosphate,Na3PO4 , for a laboratory experiment. How many grams of Na3PO4
4 answers
asked by
K
1,344 views
Calculate the mass (in grams) of the product formed when 10.1g of the underlined reactant completely reacts. Assume that there
2 answers
asked by
K
524 views
How many molecules of ammonia are produced from: 2.58x10^-4g of Hydrogen?
My balanced equation: 3H2 + N2 = 2NH3 I worked this
4 answers
asked by
K
515 views
My balanced equation is:
a) 2C8H18(g) + 25O2(g) -> 16CO2(g) + 18H2O(g) b) 0.290 mol of octane is allowed to react with 0.670mol
5 answers
asked by
K
8,019 views
Aluminum reacts with chlorine gas to form aluminum chloride via the following reaction:
2Al(s) + 3Cl2(g) -> 2AlCl3(s) You are
4 answers
asked by
K
2,020 views
Help on part "c":
The forensic technician at a crime scene has just prepared a luminol stock solution by adding 19.0g of luminol
3 answers
asked by
K
911 views
I was just wondering if someone would be able to critique my answers for the following Chem questions? they range from pretty
10 answers
asked by
K
1,050 views
A cylinder with a movable piston contains 2.00g of helium, He, at room temperature. More helium was added to the cylinder and
7 answers
asked by
K
5,071 views
Butane, C4H10, is a component of natural gas that is used as fuel for cigarette lighters. The balanced equation of the complete
4 answers
asked by
K
1,808 views
The mass of an electron is 9.11*10^-31kg. If the de Broglie wavelength for an electron in a hydrogen atom is 3.31*10^-10m, how
4 answers
asked by
K
1,600 views
The electron from a hydrogen atom drops from an excited state into the ground state. When an electron drops into a lower-energy
10 answers
asked by
K
10,037 views
The mass of a golf ball is 45.9g. If it leaves the tee with a speed of 72.0 m/s, what is its corresponding wavelength?
Express
7 answers
asked by
K
13,652 views
I just have a couple of questions that I need some help with:
1) A 0.22-caliber handgun fires a 27g bullet at a velocity of
15 answers
asked by
K
844 views
if you were to draw a Lewis dot structure for HOCl...would it be H:Cl:O: (with double dots above & below the Oxygen & Chlorine)
3 answers
asked by
K
1,132 views
Consider the relation shown for the radius of the species indicated. Which choice presents a valid comparison?
a) Na > Na+ b)
4 answers
asked by
K
1,615 views
Consider the following neutral electron configurations in which 'n' has a constant value. Which configuration would belong to
5 answers
asked by
K
5,067 views
Which of the following elements has the highest first ionization energy?
Element then radius (pm): X = 105pm Y = 175pm Z = 274pm
4 answers
asked by
K
1,376 views
Could someone please tell me if I am correct on the following???:
Pick the larger species from each of the following pairs. Sr or
4 answers
asked by
K
1,550 views
I just have one more question regarding electron configurations for the following ions:
Mo^3+ V^3+ I cannot understand why my
7 answers
asked by
K
671 views
Which answer best describes an O_3/ozone molecule:
1. Each atom in ozone is connected to another atom by 1.5 bonds. 2.The double
3 answers
asked by
K
1,416 views
If NO3- has 3 resonance structures, but only one has to be written, where does the extra electron, making there then be 24
1 answer
asked by
K
442 views
I kind of need some guidance with "PART C" below:
A) The bond angles in CH4 are 109.5degrees, while the bond angles in NH3 are
2 answers
asked by
K
512 views
kind of need some guidance with "PART C" below:
A) The bond angles in CH4 are 109.5degrees, while the bond angles in NH3 are 107
3 answers
asked by
K
606 views
What are the expected bond angles in ICl4+ (or) ICl_4^+ ??
I think that I have the stucture drawn correcty: I is the central atom
10 answers
asked by
K
14,294 views
Which statement best describes the polarity of SF_4Cl_2?? (or: SF4Cl2, if that helps more)
1. Always polar. 2. Always nonpolar.
10 answers
asked by
K
12,401 views
One other question that I am really not 100% sure on:
how do I draw the electron-dot structure for: CHClO. I "think" that CHClO
7 answers
asked by
K
835 views
You are a researcher for a golf club manufacturer. You are given two identical looking cubes of a metal alloy. You are informed
5 answers
asked by
K
5,099 views
Info:
The atoms of crystalline solid pack together into a three-dimensional array of many small repeating units called unit
2 answers
asked by
K
1,016 views
the nuclide 232 Th 90 is radioactive. when one of the atoms decays, a series of alpha and beta particle emission occurs, taking
3 answers
asked by
Gabe
1,024 views
What is the major product from an elimination reaction starting with 2-bromo-1-methylcyclohexane?
would it be: a)
10 answers
asked by
k
1,165 views
1. How many moles of water can be made from 4 moles of oxygen gas and
16 moles of hydrogen gas? What is the limiting reagent? 2.
2 answers
asked by
Anonymous
1,573 views
Show that when pH = pKa, the maximum buffer capacity (at 298.15 K) is given by: âmax = 0.576C
where C is the total concentration
1 answer
asked by
JOE
382 views
A cylinder with a movable piston contains 2.00 of helium, , at room temperature. More helium was added to the cylinder and the
3 answers
asked by
Kara
1,148 views
Calculate the density of oxygen, , under each of the following conditions:
STP 1.00atm and 25.0 degrees celsius Express your
4 answers
asked by
Kara
1,113 views
To identify a diatomic gas (), a researcher carried out the following experiment: She weighed an empty 1.00- bulb, then filled
4 answers
asked by
Kara
514 views
To identify a diatomic gas (X_2), a researcher carried out the following experiment: She weighed an empty 1.00-L bulb, then
6 answers
asked by
Kara
595 views
To identify a diatomic gas (), a researcher carried out the following experiment: She weighed an empty 1.00- bulb, then filled
2 answers
asked by
Kara
721 views
is NH3 a base or an acid how do u tell?
1 answer
asked by
brian
289 views
Confirm that the experimentally observed electronic configuration of K, 1s2 2s2 2p6 3s2 3p6 4s1 is energetically more stable
5 answers
asked by
Kimora
1,334 views
I don't understand how to find the formula of a hydrate. Here's one of the question. if you guide me through it I think I'll be
4 answers
asked by
Lena
1,183 views
Vapor pressure is the pressure exerted by a vapor when condensation:
A. < B. = C. > evaporation over its liquid in a closed
5 answers
asked by
joey
534 views
Evaporation is an
A.endothermic B.exothermic process, because when a substance evaporates it must A. absorb B. release energy
5 answers
asked by
joey
453 views
A particular household ammonia solution (d= 0.97g/mL) is 6.8% NH3 by mass.
How many milliliters of this solution should be
2 answers
asked by
help!!!
592 views
Calculate the pH of solution made by combining 75.0 mL of 0.10 M formic acid with 30.0 mL of 0.25 M KOH. (Ka for formic acid,
4 answers
asked by
Peter
526 views
Calculate the hydrogen ion concentration of a 2.30×10^-1 M solution of the strong base RbOH. Round your answer to 3 significant
2 answers
asked by
ray
502 views
Calculate the equilibrium constant for the weak base CH3NH2, if a solution of the base with an initial concentration of
2 answers
asked by
harry
868 views
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