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Magnetic Field Question - A negatively charged dust particle is moving?
from left to right in a uniform magnetic field. The direction of the magnetic field is pointing up. What will be the direction of the magnetic force on the dust particle?
1 AnswerPhysics5 years agoPhysics Question?
Two charged smoke particles exert a force of 8.0E-5 N on each other. What will be the force if they are moved so they are 1/2.0 as far apart? n.b. give your answer in Newtons.
2 AnswersPhysics5 years agoPhysics Questions - Electric Fields?
A charged object of mass 4 g and charge 10 µC is released from rest in a uniform electric field and accelerates a rate of 790 m/s2. What is the magnitude of the electric field? n.b. give your answer in N/C to 3 s.f
1 AnswerPhysics5 years agoPhysics Question - Coulomb's Law?
Calculate the magnitude of the electric field at one corner of a square 0.3 m on a side if the other three corners are occupied by 46.0µC charges. n.b. give your answer in N/C
1 AnswerPhysics5 years agoA child in a boat throws a 380.0 g package horizontally out of the boat, with a speed of 11.0 m/s.?
A child in a boat throws a 380.0 g package horizontally out of the boat, with a speed of 11.0 m/s. Calculate the speed of the boat immediately afterwards (in cm/s), assuming it was initially at rest. The mass of the child is 48.3 kg and that of the boat is 97.0 kg.
2 AnswersPhysics6 years agoPHYSICS QUESTION - An 116.0 kg astronaut is motionless in space far away from the Earth and his spaceship.?
An 116.0 kg astronaut is motionless in space far away from the Earth and his spaceship. He's holding a container of minerals he's collected, which has a mass of 1.8 kg. He decides to throw the container away from him and manages to move in the opposite direction at a speed of 0.1 m/s relative to his rest position. At what speed (in m/s) did he throw the container? Give your answer as a positive value without including a sign
Physics6 years agopOH 1.0 x 10^-5 M HCl?
1 AnswerChemistry6 years agogiven the molar enthalpy of combustion of ethanol (C2H5OH) is -1368.54 kJ/mol,?
given the molar enthalpy of combustion of ethanol (C2H5OH) is -1368.54 kJ/mol, how much heat in kilojuoules will be released by the combustion of 6.5 g at standard pressure?
1 AnswerChemistry6 years agoConsider the following reaction. Mg(s)+2HCl(aq)->MgCl2(aq)+H2(g?
Magnesium is reduced by gaining electrons, oxidized by gaining electrons, oxidized by losing electrons or reduced by losing electrons?
1 AnswerChemistry6 years agobalance fe+3 + sn+2 ---->Fe+2 + sn+4?
1 AnswerChemistry6 years agoElectrochemistry Questions - Write out the NET ionic equations ......?
The data for all of these questions is in the attached photo:
1.) Write out the NET equations for the reactions that were observed to be spontaneous.
2.) If the forward reaction is spontaneous, will the reverse reaction be spontaneous? Explain.
3.) Based on your observations, what can be said about the reaction between a metal and its aqueous ion? 4.)List the metallic ions in order with those that have the greatest tendency to form metals at the top.
5.)List the metals in order with those that have the greatest tendency to form positive ions at the top.
6.) What noticeable observation can you make when comparing the two lists from #4 and #5?
7.)Which species was the strongest reducing agent?
8.)Which species was the strongest oxidizing agent?
9.)Which species was the weakest reducing agent? ...the weakest oxidizing agent?
Also for each of the spontaneous reactions write the half-reactions and indicate which half-reaction is a reduction half-reaction and which is an oxidation half-reaction.
Please help me!!
Thanks.
1 AnswerChemistry6 years agoHess's Law Question?
Use Hess' Law to calculate enthalpy of reaction for the following equation:
2 N2(g) + 5 O2(g) → 2 N2O5(g)
Given:
2 H2(g) + O2(g) → 2 H2O(l) ΔH = -571.6 kJ/mol
N2O5(g) + H2O(l) → 2 HNO3(l) ΔH = -76.6 kJ/mol
1/2 N2(g) + 3/2 O2(g) + 1/2 H2(g) → HNO3(l) ΔH = -174.1 kJ/mol
Question 3 - Using standard enthalpies of formation, determine the ΔH reaction for the following equations:
Fe2O3(s) + 3 CO(g) → 3 CO2(g) + 2 Fe(s)
2 CH3OH(l) + 3 O2(g) → 2 CO2(g) + 4 H2O(g)
Standard Enthalpies of Formation
Compound ΔHf (kJ/mol)
Fe2O3(s) -826.0
CO(g) -110.5
CO2(g) -393.5
CH3OH(l) -238.4
H2O(g) -241.8
1 AnswerChemistry6 years agoHess's Law Question - Iron is made from a reaction of....?
Iron is made from a reaction of iron oxide with carbon monoxide in the following reaction:
Fe2O3(s) + 3 CO(g) → 2 Fe(s) + 3 CO2(g)
Using Hess' Law, calculate the enthalpy of reaction given:
C(s) + O2(g) → CO2(g) ΔH = -393 kJ/mol
2 Fe(s) + 3/2 O2(g) → Fe2O3(s) ΔH = -822 kJ/mol
C(s) + 1/2 O2(g) → CO(g) ΔH = -111 kJ/mol
1 AnswerChemistry6 years agoEquilibrium Question - The following reaction is at equilibrium at 500 oC...?
The following reaction is at equilibrium at 500 oC
CH4(g) + H2O(g)CO(g) + 3 H2(g)
Equilibrium concentrations were found to be:
[CH4(g)] = 2.46 x 10-3 M
[H2O(g)] = 4.97 x 10-3 M
[CO(g)] = 4.55 x 10-3 M
[H2(g)] = 2.20 x 10-3 M
Calculate the equilibrium constant for this reaction
2 AnswersChemistry6 years agoAcid and Base Question - Identify the acid, its conjugate base...?
Identify the acid, its conjugate base, the base and its conjugate acid in the following reaction:
H3PO4(aq) + NH3(aq) <==> H2PO4-(aq) + NH4+(aq)
2 AnswersChemistry6 years agoAcids and Bases Question - Because rain washes pollutants out of the air....?
Because rain washes pollutants out of the air, many Ontario lakes are undergoing changes in pH. The water in one such lake was found to have a hydronium ion concentration of 3.2 x 10-5 M. What is the pH of this lake? Is it considered acidic or basic?
1 AnswerChemistry6 years agoAcids and Base Question - A 0.20 M solution of hydrofluoric acid....?
A 0.20 M solution of hydrofluoric acid (HF(aq)) has a pH of 3.96 at 25 oC. Calculate the Ka and Percent Ionization of hydrofluoric acid.
HF(aq) + H2O(l) <==> F-(aq) + H3O+(aq)
2 AnswersChemistry6 years ago