Which element is a noble gas? A. W B. Ar C. N D. Er

How many grams of P2Cl5 are produced if 2.00 moles of P reacts with an excess of Cl2?

Roman55 [17]

Answer:

$m_{P_2Cl_5 }=239.2125gP_2Cl_5$

Explanation:

Hello there!

In this case, according to the reaction:

$4P+5Cl_2\rightarrow 2P_2Cl_5$

Thus, since there is a 4:2 mole ratio of P to P2Cl5 and the molar mass of the later is 239.2125 g/mol, we obtain the following mass as the produced one:

$m_{P_2Cl_5 }=2.00molP*\frac{2molP_2Cl_5}{4molP} *\frac{239.2125gP_2Cl_5 }{1molP_2Cl_5} \\\\m_{P_2Cl_5 }=239.2125gP_2Cl_5$

Regards!

5 0

3 years ago

Help on science please!

erik [133]

Answer:

See explanation.

Explanation:

1. Forrest: From 425,000,000 to 300,000,000 is a change of 125,000,000. Divide the 125,000,000 by 425,000,000 to get the percent change:

125,000,000 / 425,000,000 = .294, which is a 29.4% change, a decrease.

2. Population: From 4,500 to 326,500,000 is a change of 326,495,500. Divide 326,495,500 by 4,500 to get the percent change.

326,495,500 / 4,500 = 72,554.55 which is a change of 7,255,455% change, an increase.

3. Conclusion: The growth in population required living area. People needed farms, houses, cities, and communities to live in. Forests were cleared to make room for the people to live. Forests are also used to provide building materials. The population increase contributed to the decrease in forest lands.

6 0

3 years ago

The flask contains 10.0 mL of HCl and a few drops of phenolphthalein indicator. The buret contains 0.160 M NaOH. It requires 18.

olchik [2.2K]

Answer:

Approximately $0.291\; \rm M$ (rounded to two significant figures.)

Explanation:

The unit of concentration $\rm M$ is the same as $\rm mol \cdot L^{-1}$ (moles per liter.) On the other hand, the volume of both the $\rm NaOH$ solution and the original $\rm HCl$ solution here are in milliliters. Convert these two volumes to liters:

$V(\mathrm{NaOH}) = 18.2\; \rm mL = 18.2 \times 10^{-3}\; \rm L = 0.0182\; \rm L$ .
$V(\text{$\mathrm{HCl}$, original}) = 10.0\; \rm mL = 10.0\times 10^{-3}\; \rm L = 0.0100\; \rm L$ .

Calculate the number of moles of $\rm NaOH$ in that $0.0182\; \rm L$ of $0.160\; \rm M$ solution:

$\begin{aligned} n(\mathrm{NaOH}) &= c(\mathrm{NaOH})\cdot V(\mathrm{NaOH})\\ &= 0.160\; \rm mol \cdot L^{-1} \times 0.0182\; \rm L \approx 0.00291\; \rm mol\end{aligned}$ .

$\rm HCl$ reacts with $\rm NaOH$ at a one-to-one ratio:

$\rm HCl\; (aq) + NaOH\; (aq) \to NaCl\; (aq) + H_2O\; (l)$ .

Coefficient ratio:

$\displaystyle \frac{n(\mathrm{HCl})}{n(\mathrm{NaOH})} = 1$ .

In other words, one mole of $\rm NaOH$ would neutralize exactly one mole of $\rm HCl$ . In this titration, $0.291\; \rm mol$ of $\rm NaOH\!$ was required. Therefore, the same amount of $\rm HC$ should be present in the original solution:

$\begin{aligned}&n(\text{$\mathrm{HCl}$, original})\\ &= n(\mathrm{NaOH})\cdot \frac{n(\mathrm{HCl})}{n(\mathrm{NaOH})} \\ &\approx 0.00291\; \rm mol \times 1 = 0.00291\; \rm mol\end{aligned}$ .

Calculate the concentration of the original $\rm HCl$ solution:

$\displaystyle c(\text{$\mathrm{HCl}$, original}) = \frac{n(\text{$\mathrm{HCl}$, original})}{V(\text{$\mathrm{HCl}$, original})} \approx \frac{0.00291\; \rm mol}{0.0100\; \rm L} \approx 0.291\; \rm M$ .

5 0

3 years ago

When the pressure that a gas exerts on a sealed container changes from 22.5 psi to ? psi, the temperature changes from 110 degre

natta225 [31]

Using Gay-Lussac's Law, pressure is proportional to (absolute) temperature in Kelvin. We first convert the temperature values to Kelvin: 110 C = 383.15 K, while 65 C = 338.15 K.
P1/T1 = P2/T2
22.5/383.15 = P2/338.15
P2 = 19.9 psi

8 0

3 years ago

PLZ HELP! How do you think changing the angle of a ramp will affect work done?

kogti [31]

Answer: The steepness of a ramp affects it by making it easier or harder.

Explanation: It's a bit situational. If you were going up a steep ramp with a heavy load, it will increase the work necessary, whereas if you were going down a ramp, it would decrease the work necessary. If you need this simply put, think about biking up and down a hill. It would be easier going down than up.

6 0

3 years ago