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
Answer:
The scaling factor is 5.
Explanation:
Hello there!
In this case, since the scaling factor is defined as the ratio of the molar mass of the molecular formula (complete) to the empirical formula (simplified), it is possible to compute it for the empirical formula of CH2O whose molar mass is 30 g/mol (12+2+16) as shown below:
Therefore, we can also infer that the molecular formula would be:
Best regards!
<span>By definition:
pH = pKa + log [acetate]/ [acetic acid]
so
5.02 = 4.74 + log [acetate] / 10 mmole
10mmole = 10/1000 = 0.01 mole
5.02 = 4.74 + log [acetate] / 0.01
5.02 - 4.74 = 0.28 = log [acetate] /0.01
10^0.28 = </span><span>1.90546</span> = [acetate] / 0.01 <span>
[acetate] = 0.019 mole
= 19 millimoles
</span>
Answer:
7,94 minutes
Explanation:
If the descomposition of HBr(gr) into elemental species have a rate constant, then this reaction belongs to a zero-order reaction kinetics, where the r<em>eaction rate does not depend on the concentration of the reactants. </em>
For the zero-order reactions, concentration-time equation can be written as follows:
[A] = - Kt + [Ao]
where:
- [A]: concentration of the reactant A at the <em>t </em>time,
- [A]o: initial concentration of the reactant A,
- K: rate constant,
- t: elapsed time of the reaction
<u>To solve the problem, we just replace our data in the concentration-time equation, and we clear the value of t.</u>
Data:
K = 4.2 ×10−3atm/s,
[A]o=[HBr]o= 2 atm,
[A]=[HBr]=0 atm (all HBr(g) is gone)
<em>We clear the incognita :</em>
[A] = - Kt + [Ao]............. Kt = [Ao] - [A]
t = ([Ao] - [A])/K
<em>We replace the numerical values:</em>
t = (2 atm - 0 atm)/4.2 ×10−3atm/s = 476,19 s = 7,94 minutes
So, we need 7,94 minutes to achieve complete conversion into elements ([HBr]=0).
M=260 g
M=414.215 g/mol
n=m/M
n=260 g / 414.215 g/mol = 0.6277 mol
