Answer:
2Al+ 6HNO3 ---- 3H2 + 2Al(NO3)3
Explanation:
Put coefficient a,b,c, and d for calculation:
a Al + b HNO3 = c H2 + d Al(NO3)3
for Al: a = d
for H: b = 2c
for N: b = 3d
for O: 3b = 9d
Suppose a=1, then d=1, b=3, c=3/2
multiply 2 to make all natural number, a=2, then b=6, c=3, d=2
<span>Answer:
For this problem, you would need to know the specific heat of water, that is, the amount of energy required to raise the temperature of 1 g of water by 1 degree C. The formula is q = c X m X delta T, where q is the specific heat of water, m is the mass and delta T is the change in temperature. If we look up the specific heat of water, we find it is 4.184 J/(g X degree C). The temperature of the water went up 20 degrees.
4.184 x 713 x 20.0 = 59700 J to 3 significant digits, or 59.7 kJ.
Now, that is the energy to form B2O3 from 1 gram of boron. If we want kJ/mole, we need to do a little more work.
To find the number of moles of Boron contained in 1 gram, we need to know the gram atomic mass of Boron, which is 10.811. Dividing 1 gram of boron by 10.811 gives us .0925 moles of boron. Since it takes 2 moles of boron to make 1 mole B2O3, we would divide the number of moles of boron by two to get the number of moles of B2O3.
.0925/2 = .0462 moles...so you would divide the energy in KJ by the number of moles to get KJ/mole. 59.7/.0462 = 1290 KJ/mole.</span>
Explanation:
An object in motion <u>stays</u> <u>at</u> motion An object <u>at</u> <u>rest</u> stays at rest unless acted by an <u>external</u> force.
[ Newton's 1st law of motion ]
Answer:
2 Fe(iii)2O3 + 3 C ==> 2 Fe + 3 CO2
Explanation:
First of all, you have to translate the words into an equation.
Fe(iii)2O3 + C ==> Fe + CO2
The easiest way to tackle this is to start with the Oxygens and balance them. They must balance by going to the greatest common factor which is 6. So you multiply the molecule by whatever it takes to get the Oxygens to 6
2 Fe(iii)2O3 + C ==> Fe + 3 CO2
Now work on the irons. There 2 on the left and just 1 on the right. So you need to multiply the iron by 2.
2 Fe(iii)2O3 + C ==> 2 Fe + 3 CO2
Finally it is the turn of the carbons. There are 3 on the right, so you must make the carbon on the left = 3
2 Fe(iii)2O3 + 3 C ==> 2 Fe + 3 CO2
And you are done.
