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2 years ago

The less energy a wave has, the greater its amplitude. True or False

Chemistry

1 answer:

S_A_V [24]2 years ago

6 0

Answer:

true

Explanation:

the more energy a wave has the greater the amplitude is

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A scientist finds an organism that cannot move. It has many cells and get food from its environment. In which Kingdom does it

Allisa [31]

An organism that does not move on its own and makes food from its environment is a producer.

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3 years ago

20cm of 0.09M solution of H2SO4. requires 30cm of NaOH for complete neutralization. Calculate the

kirill115 [55]

Answer:

Choice A: approximately $0.12\; \rm M$ .

Explanation:

Note that the unit of concentration, $\rm M$ , typically refers to moles per liter (that is: $1\; \rm M = 1\; \rm mol\cdot L^{-1}$ .)

On the other hand, the volume of the two solutions in this question are apparently given in $\rm cm^3$ , which is the same as $\rm mL$ (that is: $1\; \rm cm^{3} = 1\; \rm mL$ .) Convert the unit of volume to liters:

$V(\mathrm{H_2SO_4}) = 20\; \rm cm^{3} = 20 \times 10^{-3}\; \rm L = 0.02\; \rm L$ .
$V(\mathrm{NaOH}) = 30\; \rm cm^{3} = 30 \times 10^{-3}\; \rm L = 0.03\; \rm L$ .

Calculate the number of moles of $\rm H_2SO_4$ formula units in that $0.02\; \rm L$ of the $0.09\; \rm M$ solution:

$\begin{aligned}n(\mathrm{H_2SO_4}) &= c(\mathrm{H_2SO_4}) \cdot V(\mathrm{H_2SO_4})\\ &= 0.02 \; \rm L \times 0.09 \; \rm mol\cdot L^{-1} = 0.0018\; \rm mol \end{aligned}$ .

Note that $\rm H_2SO_4$ (sulfuric acid) is a diprotic acid. When one mole of $\rm H_2SO_4$ completely dissolves in water, two moles of $\rm H^{+}$ ions will be released.

On the other hand, $\rm NaOH$ (sodium hydroxide) is a monoprotic base. When one mole of $\rm NaOH$ formula units completely dissolve in water, only one mole of $\rm OH^{-}$ ions will be released.

$\rm H^{+}$ ions and $\rm OH^{-}$ ions neutralize each other at a one-to-one ratio. Therefore, when one mole of the diprotic acid $\rm H_2SO_4$ dissolves in water completely, it will take two moles of $\rm OH^{-}$ to neutralize that two moles of $\rm H^{+}$ produced. On the other hand, two moles formula units of the monoprotic base $\rm NaOH$ will be required to produce that two moles of $\rm OH^{-}$ . Therefore, $\rm NaOH$ and $\rm H_2SO_4$ formula units would neutralize each other at a two-to-one ratio.

$\rm H_2SO_4 + 2\; NaOH \to Na_2SO_4 + 2\; H_2O$ .

$\displaystyle \frac{n(\mathrm{NaOH})}{n(\mathrm{H_2SO_4})} = \frac{2}{1} = 2$ .

Previous calculations show that $0.0018\; \rm mol$ of $\rm H_2SO_4$ was produced. Calculate the number of moles of $\rm NaOH$ formula units required to neutralize that

$\begin{aligned}n(\mathrm{NaOH}) &= \frac{n(\mathrm{NaOH})}{n(\mathrm{H_2SO_4})}\cdot n(\mathrm{H_2SO_4}) \\&= 2 \times 0.0018\; \rm mol = 0.0036\; \rm mol\end{aligned}$ .

Calculate the concentration of a $0.03\; \rm L$ solution that contains exactly $0.0036\; \rm mol$ of $\rm NaOH$ formula units:

$\begin{aligned}c(\mathrm{NaOH}) &= \frac{n(\mathrm{NaOH})}{V(\mathrm{NaOH})} = \frac{0.0036\; \rm mol}{0.03\; \rm L} = 0.12\; \rm mol \cdot L^{-1}\end{aligned}$ .

3 0

2 years ago

What is the vapor pressure of a solution in which the mole fraction of the solute is 0.200 and the vapor pressure of the pure so

Ulleksa [173]

Answer: The vapor pressure of a solution in which the mole fraction of the solute is 0.200 is 80.0 torr

Explanation:

As the relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.

The formula for relative lowering of vapor pressure will be,

$\frac{p^o-p_s}{p^o}=i\times x_2$

where,

$p^0$ = vapor pressure of pure solvent = 100.0 torr

$p_s$ = vapor pressure of solution = ?

i = Van'T Hoff factor = 1 for nonvolatile, nonelectrolyte solute

$x_2$ = mole fraction of solute = 0.200

$\frac{100.0-p_s}{100.0}=1\times 0.200$

$p_s=80.0torr$

The vapor pressure of a solution in which the mole fraction of the solute is 0.200 is 80.0 torr

7 0

2 years ago

Silver metal is added to a solution of lead(II) nitrate. What is the balanced chemical reaction

CaHeK987 [17]

Answer:

When silver metal is reacted with the solution of lead nitrate at that time silver nitrate is formed along with lead metal.

Explanation:

The balanced equation of the given reactio is

Pb(NO3)2 + 2Ag= 2AgNO3+ Pb

In this reaction lead nitrate Pb(NO3)2 reacts with silver(Ag) to form a salt Silver nitrate(AgNO3) along with lead metal(Pb).

5 0

2 years ago

Read 2 more answers

What is the maximum mass of glucose (C6H12O6) that can be burned in 10 g of oxygen?

Dahasolnce [82]

$C_6H_{12}O_6 + 6 \ O_2 \to 6 \ CO_2 + 6 \ H_2O$
1 mole of glucose : 6 moles of oxygen

First calculate the number of moles of oxygen in 10 g:
$M=32 \ \frac{g}{mol} \\
m=10 \ g \\
n=\frac{10 \ g}{32 \ \frac{g}{mol}}=0.3125 \ mol$

1 mole of glucose reacts with 6 moles of oxygen
x moles of glucose reacts with 0.3125 moles of oxygen
$x=\frac{1 \ mol \cdot 0.3125 \ mol}{6 \ mol} = \frac{3125}{60000} \ mol= \frac{5}{96} \ mol$

Now calculate the mass of 5/96 moles of glucose.
$M=180 \ \frac{g}{mol} \\
n=\frac{5}{96} \ mol \\
m=180 \ \frac{g}{mol} \cdot \frac{5}{96} \ mol=\frac{900}{96} \ g=9.375 \ g$

The maximum mass of glucose that can be burned in 10 g of oxygen is 9.375 g.

5 0

2 years ago