Recent content by rahmatkat

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    Why does the reaction between acid and aluminium start slow and then speed up?

    Oh, So Aluminium Oxide did form? As for the reaction, the oxygen present in the Alumium Oxide react first with the acid and when that Oxygen dissapear, the acid then react with Aluminium, is that rihgt?
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    Why does the reaction between acid and aluminium start slow and then speed up?

    Oh, I get it now, aluminium react with oxygen gas in the air and produce Aluminium Oxide forming in the outside part of an aluminium metal right? So when that aluminium metal is reacted with an acid, Aluminium Oxide reacts first with the acid and when it finished reacting with it, the acid then...
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    Why does the reaction between acid and aluminium start slow and then speed up?

    Well, my idea is that it has a high melting and boiling point and its resist corrosion, unfortunately my answer above is wrong and i don't have any other idea why it reacts slowly with acid at first and then faster.
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    Why does the reaction between acid and aluminium start slow and then speed up?

    Can anyone help me with this homework question? it was like this: The reaction between the acid and aluminium is slow in the beginning and then gets faster. Give an explanation for this observation. Thanks.
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    Is Velocity Conserved in a Falling Balls Collision Experiment?

    So I have to find out the kinectic energy of the two ball's as well, I think that were i got everything wrong 'cause I was only trying to find the velocity of the balls. Thank for the help.
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    Is Velocity Conserved in a Falling Balls Collision Experiment?

    Hi there, can anyone help me with this problem, I'll be grateful to received your help. It was like this, we were doing an experiment on collision and this is how it goes; We place a ramp on table and a sheet of paper at the bottom of the table but close to the edge. Then we put two...
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    Photoelectric effect and work function

    Explain why the backing volts depends on the frequency of light but not on the intensity.
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    What is the mass of water that will react with 4.0g of pure calcium metal?

    sorry but I don't have a textbook, that why I was asking for your help guys. I know that it sounds funny but in our school we weren't given any textbooks, we just have to rely on our teachers notes, the reason is that we don't have much, and another problem is that i left my form five chemistry...
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    What is the mass of water that will react with 4.0g of pure calcium metal?

    I have add the formula weight of water and calcium, and I don't know how to convert mole ratio to mass ratio cause i forgot how.
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    What is the mass of water that will react with 4.0g of pure calcium metal?

    I have an assignment that i have to do this weekend and i was wondering if anyone can help me with it, here's the only question that I don't understand; 1)calculate the mass of the water that will react completely with 4.0g of pure calcium metal according to the following equation: Ca(s) +...
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    Frying Pans vs. Hammers: Which Drives Nails Farther with Same Mass and Velocity?

    Sorry, i was anwering someones question, maybe i got on the wrong side of the track. By the way, What is the formula for Centripital Force? it new to me.
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    Formula for the velocity of the centripetal force

    Thanks for you're help, anyway i have another question. What is the formula for centripital force?, our physics teacher gave us a practical to do but he forgot to give us a note on centripital force.
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    Frying Pans vs. Hammers: Which Drives Nails Farther with Same Mass and Velocity?

    I think youre wrong, though the pan and the hammer have the same mass, the hammer will drive the nail futher.
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    Formula for the velocity of the centripetal force

    Hi, can anyone please tell me the fomular for the velocity of a centripital force with the radius of 100 cm, with one revolution revolting in 0.98 seconds?
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