SOMEONE HELP ASAPP...

Should existing structures build from CCA-treated wood be removed?

Arturiano [62]

<span>There are pros and cons as to whether CCA-treated (pressure-treated) wood should be removed from existing structures, and both sides are subjective. Some of the arguments for leaving it include: *When burned, the wood can release dangerous, and sometimes, lethal fumes. *If buried in a landfill, the chemicals can soak into the ground and eventually contaminate ground water. *Removing it can expose people to arsenic *It is costly to remove an existing infrastructure that may or may not be harming people *Studies conducted within the past decade have determined structures containing CCA-treated wood pose no hazard *Studies also concluded that children who played on CCA-treated playgrounds were exposed to arsenic levels lower than those that naturally occur in drinking water Some of the arguments for removing it include: *The EPA determined that some children could face higher cancer risks from exposure to CCA-treated wood *If removed, it will need to be disposed of and, as discussed above, that creates another set of problems that could affect a community's health. A possible solution is to leave existing CCA-treated wood in place but seek viable, safe alternatives for future structures.</span>

3 0

3 years ago

For the following problem convert both the reactants to moles and balance chemical equationsThe reaction of 167 g Fe2O3 with 85.

saul85 [17]

Let's start by balancing the reaction:

$Fe_2O_3+CO\longrightarrow Fe+CO_2$

As we can see, C appears only on two comopunds, CO and CO₂, and since both have 1 C each, their coefficients have to be the same for C to be balanced. However, CO has 1 O and CO₂ has 2, so there is a difference of 1 O betwee them.

The other source of O is Fe₂O₃, that has 3 O. So, we must choose a coefficient for CO and CO₂ such that the difference between the numbers of O is a multiple of 3, that way we can fix this difference with the O from Fe₂O₃. So, we can put coefficients of 3 on both of them:

$Fe_2O_3+3CO\longrightarrow Fe+3CO_2$

That way, we maintained C balanced (3 on each side) and now we have 3 + 3 O on the left side and 6 O on the right side, so the same amount.

Now, we just have to calance Fe, but it is easy since we have it alone in Fe. Since we have 2 on the left side, it is enough to put a coefficient of 2 on Fe to get the balanced reaction:

$Fe_2O_3+3CO\longrightarrow2Fe+3CO_2$

Now, to convert from mass to number of moles, we need the molar masses of the reactants, which we can calculate from the atomic weights of the elemnts in each of them:

$M_{Fe_2O_3}=2\cdot M_{Fe}+3\cdot M_O=(2\cdot55.845+3\cdot15.9994)g/mol=159.6882g/mol$ $M_{CO}=1\cdot M_C+1\cdot M_O=(1\cdot12.0107+1\cdot15.9994)g/mol=28.0101g/mol$

Now, we can convert their masses to number of moles:

$\begin{gathered} M_{Fe_{2}O_{3}}=\frac{m_{Fe_2O_3}}{n_{Fe_{2}O_{3}}} \\ n_{Fe_2O_3}=\frac{m_{Fe_2O_3}}{M_{Fe_{2}O_{3}}}=\frac{167g}{159.6882g/mol}=1.045787\ldots mol \end{gathered}$ $\begin{gathered} M_{CO}=\frac{m_{CO}}{n_{CO}} \\ n_{CO}=\frac{m_{CO}}{M_{CO}}=\frac{85.8g}{28.0101g/mol}=3.063180\ldots mol \end{gathered}$

Now, to determine the limiting reactant, we need to divide both the number of mole by their coefficients on the balanced reaction, so we can see how many we need per reaction of each:

$\begin{gathered} Fe_2O_3\colon\frac{n_{Fe_2O_3}}{1}=\frac{1.045787\ldots mol}{1}=1.045787\ldots mol \\ CO\colon\frac{n_{CO}}{3}=\frac{3.063180\ldots mol}{3}=1.021060\ldots mol \end{gathered}$

Now, the limiting reactant is the one we have less number of moles per reaction. We can see that we have less CO than Fe₂O₃, so the limiting reactant is CO.

4 0

1 year ago

For the reaction shown, calculate how many moles of NH3 form when 16.72 moles of reactant completely reacts:

Agata [3.3K]

Answer : The moles of $NH_3$ formed are, 22.3 moles.

Explanation : Given,

Moles of $N_2H_4$ = 16.72 mol

The given chemical reaction is:

$3N_2H_4(l)\rightarrow 4NH_3(g)+2N_2(g)$

From the balanced chemical reaction, we conclude that:

As, 3 moles of $N_2H_4$ react to give 4 moles of $NH_3$

So, 16.72 moles of $N_2H_4$ react to give $\frac{4}{3}\times 16.72=22.3$ moles of $NH_3$

Therefore, the moles of $NH_3$ formed are, 22.3 moles.

8 0

4 years ago

What is the result of wave motion on water particles?

suter [353]

Answer:

A. Water particles barely move forward; they move in a circular pattern.

4 0

3 years ago

Read 2 more answers

Is the sky actually blue?

Mkey [24]

Answer:

When we look at an arbitrary point in the sky, away from the sun, we see only the light that was redirected by the atmosphere into our line of sight. Because that occurs much more often for blue light than for red, the sky appears blue. Violet light is actually scattered even a bit more strongly than blue.

Explanation:

8 0

3 years ago