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Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

Chemistry
In a certain reaction 0.20g of hydrogen gas combines with 3.20g of oxygen gas.if the relative molecular mass of the compound is 34.0 find its molecular formula (H=1,O=16).

Chemistry - Enthalpy
When a 37.00 g silver spoon, initially at room temperature, is placed into 250.0mL of 90.00oC tea, it reaches a temperature of 85.00°C. The spoon will have gained ? J of thermal energy. I got 5237.5 Joules as (mass)x(specific heat capacity)x(Temperature change)=Heat, which ...

Chemistry
What will burning of .3 liters of C2H2 produce?

chemistry
Calculate pH of 6ml of 3M HNO3 diluted to 18 litres of water

chemistry
1) Copy and complete: Two particles can react together only if they …… and the …… has enough …… to be ……. 2) What is meant by: a a successful collision? b an unsuccessful collision? 3) Reaction between magnesium and acid speeds up when: a)the concentration of ...

Chemistry
If you had a basketball that was filled with mercury, about how much would it weigh? (The density of mercury is 13.6 grams per cubic centimeter.) First Hint: If you do not know the dimensions of a basketball, you should ESTIMATE them.

Chemistry
A large balloon contains 65.0 L of helium gas at 25 °C and a pressure of 745 mm Hg. The balloon ascends to 3000 m, at which the external pressure has decreased by 30.%. What would be the volume of the balloon, assuming it expands so that the internal and external pressures ...

chemistry
Calculate the energies of the states of hydrogen atom with n=2 and n=3

Chemistry
Label the following changes as CHEMICAL or PHYSICAL change 1. Fat reacting with sodium hydroxide 2. Chemical A originally is buoyant in water; after it mixed with HCI, the new substance now sinks in water Label the following reactions as exothermic or endothermic 1. Ammonium ...

Chemistry
I am having trouble on a chemistry question for my study guide I have researched it and can't get an answer I understand can someone please help me? Describe what happened when an Ag+ combined with Na2CO3. What does this indicate?

Chemistry
What happens when equal volumes of 10^-5M of BaCl2 and 10^-5M of Na2SO4 are mixed at 25degree Celsius. Ksp of BaSO4=0.3×10^-10.

Chemistry
0.001N NaoH calculate the ph

chemistry
25cm cubed of 0.250mol per litre of potasium carbonate was nuetralized 12.5cm cubed of ethanoic acid of unknown concentration.determine concentration of the acid

chemistry
Calculate the energy required for ionization of electron from the ground state of hydrogen atom

chemistry
The reaction 2 NO(g) + O2(g) --> 2 NO2(g) is important in forming smog. Under certain conditions, the rate law for a the reaction is rate = 4.0 x 10-3 1/M2*s * [NO]2* [O2] What is the rate when [NO]=0.020 M and [O2]=0.035 M? a. 5.6 x 10-2 M/s b. 9.8 x 10-5 M/s c. 9.8 x 10-8...

chemistry
Calculate the concentration of KIO3(aq) present at the beginning of a reaction when 2.00 mL of 0.020 M KIO3(aq) is mixed with 8.00 mL of other solutions so the initial volume for the reacting mixture is 10.00 mL.

chemistry
Consider the reaction: N2(g) + 3 H2(g) --> 2 NH3(g). At a particular time, the nitrogen is being consumed at a rate of 0.60 moles/sec. At this same time, what is the rate at which ammonia is being formed? a. 3.0 mol/s b. 0.12 mol/s c. 0.30 mol/s d. 2.0 mol/s e. 1.2 mol/s

chemistry
The rate of a reaction A + 2B --> products is determined. When the concentration of A is 1.0 M, the rate of the reaction is 0.50 M/s. When the concentration of A is 0.50 M, the rate is 0.25 M/s. From this data, you can determine: a. that the reaction is second order in A. b...

chemistry
In a reaction, a chemist is observing the absorbance of CoCl2(aq) as a function of time to determine the rate at which it is being consumed in a reaction. At time t=10 s, the chemist determines that the concentration of CoCl2(aq) is 0.12 M. At time t=20 s, the chemist ...

Chemistry
why is a solution of copper sulfate and sulfuric acid required in corrosion testing? Won't the protons and the positive ions adhere to the metals surface and contaminant it?? Just a curious q. Thanks!

Chemistry
Calculate the number of grams of the indicated element in the compound. a) lead in 63.8 g PbO2 b) carbon in 1.664 g (CH3)2CO

CHECK MY CHEMISTRY WORK PLEASE ASAP
1. You have been given a sample of unknown molarity. Calculate the molarity of a solution which has been prepared by dissolving 8.75 moles of sodium chloride in enough water to produce a solution of 6.22l. 2. You have a sample which consists of 428g sodium hydroxide (NaOH) ...

Chemistry
What is an alcohol? Give a short definition. My answer: An organic compound in which one or more groups of hydroxyl is bonded to a chain of hydrocarbons. Do I need to change something of my answer to make it easier to understand? Thanks.

CHEMISTRY
You have been given a sample of unknown molarity. Calculate the molarity of a solution which has been prepared by dissolving 8.75 moles of sodium chloride in enough water to produce a solution of 6.22l. 2. You have a sample which consists of 428g sodium hydroxide (NaOH) ...

Chemistry
For the following reactions, determine the equilibrium constant equation. 1) CO2(g) + H2(g) CO(g) + H2O(g) 2) 2NO(g) + 2H2(g) N2(g) + 2H2O(g) 3) Cu(s) + 2Ag+(g) Cu2+(g) + 2Ag(s) 4) H2(g) + I2(g) 2HI(g)

Chemistry VERY DIFFICULT
Imagine you have been given a series of materials to react together and the following enthalpy change data has been recorded. Explain the terms exothermic and endothermic, and identify which of the following are exothermic and endothermic reactions. Ensure that you explain ...

Chemistry
1. You have been given a sample of unknown molarity. Calculate the molarity of a solution which has been prepared by dissolving 8.75 moles of sodium chloride in enough water to produce a solution of 6.22l. 2. You have a sample which consists of 428g sodium hydroxide (NaOH) ...

Science, Chemistry
A 1050.0 mL solution of NaOH is neutralized by 0.25 L of 2.00M Nitric Acid using Bromothymol Blue as an indicator. The concentration of the NaOH solution is 0.48M. True or False

chemistry
Calculate the energy required for ionization of electron from the ground state of hydrogen atom

chemistry
Ammonia reacts with copper(ll)oxide to give nitrogen gas, copper and steam. Balance the equation. If 18.1g of ammonia is reacted with 90.4g of coope(ll)oxide,how many moles of each reacts?,and how many grams of nitrogen are formed?

CHEMISTRY URGENT
1. You have been given a sample of unknown molarity. Calculate the molarity of a solution which has been prepared by dissolving 8.75 moles of sodium chloride in enough water to produce a solution of 6.22l. 2. You have a sample which consists of 428g sodium hydroxide (NaOH) ...

chemistry help asap please
You have been given a sample of unknown molarity. Calculate the molarity of a solution which has been prepared by dissolving 8.75 moles of sodium chloride in enough water to produce a solution of 6.22l.

CHEMISTRY
You have been given a sample of unknown molarity. Calculate the molarity of a solution which has been prepared by dissolving 8.75 moles of sodium chloride in enough water to produce a solution of 6.22l.

Chemistry
CuCO3=CuO +CO2. Find the mass of 1mole of each substance taking part in the reaction. (Ar:Cu=64,C=12,O=16). When 31g of CuCO3 is used; 1)how many grams of CO2 is formed. 2) what mass of solid remains after heating.

Science Chemistry
LIST: SODIUM CARBONATE. CALCIUM CARBONATE. ZINC SULFATE. ZINC NITRATE. (a) State a pair of chemicals from the list above that can be used to prepare zinc carbonate by precipitation reaction involving mixing 2 aqueous solutions together. (b) Write a chemical equation for the ...

Science Chemistry
LIST: SODIUM CARBONATE. CALCIUM CARBONATE. ZINC SULFATE. ZINC NITRATE. (a) State a pair of chemicals from the list above that can be used to prepare zinc carbonate by precipitation reaction involving mixing 2 aqueous solutions together. (b) Write a chemical equation for the ...

Science Chemistry
LIST: Sodium carbonate. Calcium carbonate. Zinc sulfate. Zinc nitrate. (a) State a pair of chemicals from the list above that can be used to prepare zinc carbonate by a precipitation reaction involving mixing 2 aqueous solutions together. (b) Write a chemical equation reaction...

chemistry
Calculate the maximum number of unpaired electrons that can be placed in a 6d subshell

chemistry
2Na + 2H2O---> 2NaOH + H2 Need to find the molecules of H2 Atomic wt o Na = 23 48.7 g of Na 48.71/23 = 2.12 mols Na 2.12/2 × 24. (WHERE DOES THE 24 COME FROM) = 25.44 dm^3 H. (PLEASE EXPLAIN THIS PART) = 1.06moles 1.06mols× 6.02×10^23 avagados number= 1.204 × 10^24 ...

CHEMISTRY
A 70g sample of iron ore(Fe2O3) was analyzed for Iron and found to contain 1700 Fe. Calculate the percentage of iron in the sample.

Chemistry
A 3 M HCL solution was used to generate the Co2 from the CaCO3. What would be the effect of substituting 6 M HCL for 3 M HCL? Explain

chemistry
writing blanced decomposition formula of Ammonium Carbonate

Chemistry
Given the reaction below, and your knowledge of the "Law of Conservation of Mass", what is the missing product from the chemical reaction? How do you know? Zn(s) + HCl(aq) --> ___ + ZnCl2(aq)

Chemistry
How many moles Of (Al2SO4)3 can be prepared from 2.5ml Of H2SO4

AP Chemistry
Dinitrogen pentoxide (N2O5) decomposes in chloroform as a solvent to yield NO2 and O2. The decomposition is first order with a rate constant at 45 degrees Celsius of 1.0*10^-5 s^-1.Calculate the partial pressure of O2 produced from 1.00 Liter of 0.600 M N2O5 solution at 45 ...

Chemistry
Mean titre of 0.2M sodium thiosulphate = 32.2 ml 1) Calculate number of moles of S2O32- which react in the titration 2)Calculate how many moles of I2 react with this amount of S2O3 3)How many Cu2+ ions are needed to liberate this amount of I2? Use this answer as the number of ...

chemistry
Calculatr morality of a solution containing 2.5g of K2CO3 in 1liter of solution (density of solution is 0.85 gram/ml

chemistry grade 11
ferrous sulfate was prepared by dissolution of x grams p feso4.7H20 crystals in 500 ml water. 20 ml of this solution necessities 5 ml of 0.1mol/l kmn04 for the pink color to persist. find x

chemistry
Write an equation for the reaction that take place in hydrogen sulphide gas when bubbled through a solution of zinc nitrate

chemistry
What would be made if hydrogen sulphide gas was bubbled through a solution of zinc nitrate

Chemistry
calculate number of moles of NH3 if 8g of H2 reacts in excess N2

Chemistry
NaCl [Symbol] Na + Cl2 Type of reaction: synthesis KOH + HNO3 [Symbol] HOH + KNO3 Type of reaction: double replacement Ca + S [Symbol] CaS Type of reaction: synthesis BaBr2 + Cl2 [Symbol] BaCl2 + Br2 Type of reaction: Cs2 + H2O [Symbol] CsOH + H2 Type of reaction: Na2CO [...

Chemistry
How many molecules present in 500ml of 42g NaHCO3?

chemistry
How is sulphur manufactured in a large scale

Chemistry HELP! CONFUSED!
How do you do this? please help. Thank you. A.) Suppose 2.5 grams of sodium hydrogen carbonate reacts with acetic acid, calculate how many liters of carbon dioxide gas will be produced at 22 degrees celcius and 1.10 atm. B.) Suppose 0.990 liters of carbon dioxide at 25 degrees...

Chemistry
Hello, Is there a reaction when NaNO3 is added to some H2O? Or does it just dissolves? Please explain why, thanks!

Chemistry
If I add water to NaNO3 does it make HNO3 and NaOH? For example NaNO3 + H2O -> HNO3 + NaOH is that equation correct? Please explain if it's not. Thanks!

chemistry
Hello, Is nano3 + h2o -> naoh + hno3 correct?

chemistry
Name two metals which are obtained by reducing thier oxides by heating with aluminium How is the metal oxides present in calcined/roasted ore reduced to the metal

chemistry
Name two metals which are obtained by reducing thier oxides by heating with aluminium How is the metal oxides present in calcined/roasted ore reduced to the metal

Chemistry
Is this a valid equation? NaNO3 + H2O = NaOH + HNO3 Why or why not?

chemistry AS
how do you draw the skeletal structure for (z)-pent-2-ene.

Chemistry
Hello, If I add water to a solid, how do i represent it in a equation with phases? for example the NaNO3 was the solid in this case and H2O was the liquid, does NaNO3 turns into an aqueous or stays as solid when I write the equation? Which one would be correct? 1) NaNO3(s) + ...

Chemistry
Using equation only. Show how tetraoxosulphate(IV) can be prepared industrially

Chemistry
Hello, Which one is correct? 1) NaOH(aq) + HNO3(aq) ⇋ NaNO3(aq) + H2O(l) or 2) NaNO3(s) + H2O(l) ⇋ NaOH(aq) + HNO3(aq) Thanks!!

Chemistry
Iron+CON Hydrochloric acid =?

Chemistry
Hello, Sorry to bother you all, but i have a quick question. If I needed to use heat in a reaction, for example, Ca(OH)2(s) + 2NH4Cl(s) = 2H2O(g) + 2NH3(g) + CaCl2(s) Do I need to put "+heat" on the reactant side when writing my equation? Thanks in advance! :)

chemistry
a sample of gaseous substance at 25 degrees Celsius and 0.862atm has a density of 2.6g/l. what is the molecular weight of the substance?

chemistry
if 3.15g of mercury are thermally decomposed to mercury and oxygen what mass of mercury will be produced and how many oxygen molecules will be produced [hg=208,o=16]

Chemistry
Hello, 1) What is the PH if ammonia is mixed with water vapour? 2) What is the white smoke when I heat NH4Cl with Ca(OH)2? Thanks

Chemistry
Hello, What are the phases for this equation? NaNO3 + H2O ⇋ NaOH + HNO3 Oh and can I write the equation this way as well? NaOH + HNO3 ⇋ NaNO3 + H2O Do they mean the same thing?

Chemistry
One mole of an ideal gas is allowed to expand isothermally at -29. 3degrees celcious from a volume of 4. 0L and apressure of 5. 0atm to avolume of 10. 0L and apressure of 2. 0atm. i. Draw a p-v diagram for the process. ii. Determine the work done by the fasduring expansion.

Chemistry
Hi, what is the PH for NH3 in gas form? When I tested it with PH paper it showed a number around 8-9.5, but from searching online its a higher number. I'm not sure which one is correct. Thanks

chemistry
Hi, I was wondering why is there white smoke when nh4cl and ca(oh)2 is being heated. Thanks!

Chemistry
1. A student collected the following data for a fixed volume of gas: Temperature (⁰C) Pressure (mm of Hg) 10 726 20 750 40 800 70 880 100 960 150 ??? Fill in the missing data point. Show all calculations leading to an answer.

Chemistry
Which of the following is true about oxidation reactions? A. Oxidation reactions are the principal source of energy on Earth. B. All oxidation reactions are accompanied by reduction reactions. C. The burning of wood in a fireplace and the metabolization of food by your body ...

SAT Math
All of the students who took chemistry at Groveton High School last year were juniors or seniors, as shown in the table below. If 80% of the students who took chemistry passed, then what fraction of the students in the combined junior and senior classes took chemistry? Class ...

Chemistry AP
How many mL of0.4M AgNO3 solution must be added to 200mL of0.4 M NaI in order to for 11.7 grams of AgI precipitate?

chemistry
Calculate the vapour density of a triatomic gasX if it's relative atomic mass is 16

chemistry
how many g/ml are there in 1M?

Chemistry
What mass of zinc metal would be needed to produce 0.5 litre of hydrogen gas from dilute HCl

chemistry
The label of a bottle containing a solution So of hydrochloric acid carries the following indications :hydrochloric acid of density 1190g/l percentage by mass 37%. We introduce a volume V=4.2ml of So in a volumetric flask of volume 500ml containing about 100ml of distilled ...

chemistry
One has a solution Sa of ethanoic acid of concentration Ca=1×10^-2 mol/l and pH=3.4  One mixes a volume Va=60ml of the solution Sa of ethanoic acid with a volume Vb1=20ml of the Sb1 solution of ammonia of concentration Cb1=2×10^-2 mol/l. The pH is 5 One has a soutions of ...

Chemistry
An ion x3-has 16 neutrons and an electronic configuration of2.8.8 determine 1]th number of protons in an atom x 2]the atomic mass of x

Chemistry
a domestic cleaner contains concentrated hydrochloric acid as the active ingredient. a titration experiment was carried out to determine the concentration of hydrochloric acid in the domestic cleanser. 20.0mL of the cleanser were diluted to 250.0mL with distilled water. 25.0mL...

Chemistry
A given volume of ozone diffused from a certain apparatus in 96seconds calculate the time taken by an equal volume of carbonoxide to diffuse under the same condition?

Chemistry
Discuss the expansion of an ideal gas and changes in thermodynamic properties (3 marks)

Applied Science Chemistry
A 0.5g mixture of Cu and CuO was treated with hydrogen at elevated temperature. CuO was reduced to Cu. Q1.) write a balanced equation for the reaction Q2.) before the experment, calculate the minimum amount in mole of hydrogen required to ensure the reduction is completed

chemistry
One has a solution Sa of ethanoic acid of concentration Ca=1×10^-2 mol/l and pH=3.4 One mixes a volume Va=60ml of the solution Sa of ethanoic acid with a volume Vb1=20ml of the Sb1 solution of ammonia of concentration Cb1=2×10^-2 mol/l. The pH is 5 One has a soutions of weak...

chemistry
The label of a bottle containing a solution So of hydrochloric acid carries the following indications :hydrochloric acid of density 1190g/l percentage by mass 37%. We introduce a volume V=4.2ml of So in a volumetric flask of volume 500ml containing about 100ml of distilled ...

chemistry
In equation He +Br2------>2HI why chemical rate of Br2 is taken as 1/2 . It's a reversible reaction. Please explain in detail. While H2 rate is taken as 1 why?

chemistry
A domestic cleanser contains concentrated HCl as the active ingredient. A titration experiment was carried out to determine the concentration of HCl in the domestic cleanser. 20.0 ml of the cleanser were diluted to 250.0 ml with distilled water. 25.0 ml of the diluted cleanser...

chemistry
A) A solution was prepared by dissolving 1.113 g of MgCl2 into water and made up to 50.0 ml, calculate the molar concentration of the solution. B) A 250.0 ml of 0.50 M solution of Na3PO2 solution was prepared by diluting 2.5 M of stock solution. Calculate the volume of stock ...

Chemistry
How many litres nitric acid 70% w/w and how many litres of water do I need to prepare a 47 v% nitric acid solution. Please help.

Chemistry
Hi, How do you know how many ligands a metal ion needs to form a complex ion? So for example, with (Fe(H20)6)2+, how am I supposed to know that the Fe needs 6 H20's, rather than 4? Thank you!

Chemistry
I have asked this question before but I was not clear enough. I want to prepare a 37% w/w solution (in water)of sulfuric acid from 96% sulfuric acid. I need around 500ml, I know it won't be exactly that, I want to know how to use the conversion using density, I've been shown a...

chemistry
A 0.50 g mixture of Cu and CuO was treated with hydrogen at elevated temperature. CuO was reduced to Cu . (b) Before the experiment, calculate the minimum amount (in mole) of hydrogen required to ensure the reduction is completed. (3 marks) (c) After passing with in excess ...

Science Chemistry
Phosphorous (P) is an indispensable nutrient in food production. According to the estimates, mineral phosphorous resources will end up within 50 years and consequently new sources of P has to be found. A human excretes 2,2 g of phosphorous (P) per day on average. In ...

Science Chemistry
according to the reaction below: 4 NO + 3 O2 + 2 H2O → 4 HNO3 a) 0,001 g of NO dissolves into 1 liter of rainwater and all of it transforms into nitric acid. What is the molar concentration of nitric acid in the rainwater? b) Supposing that no other acids are dissolved in ...

Science Chemistry
The elementary analysis of 22 g hydrocarbon sample results in 18 g C and 4 g H. a) Choose the correct chemical formula of the hydrocarbon: i) CH4 ii) C2H4 iii) C3H8 b) What is the amount of CO2 in grams formed by the total combustion of hydrocarbon? Assume complete combustion...

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