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dimulka [17.4K]

3 years ago

12

Rhett is solving the quadratic equation 0= x2 – 2x – 3 using the quadratic formula. Which shows the correct substitution of the

values a, b, and c into the quadratic formula?

1 answer:

bekas [8.4K]3 years ago

8 0

The correct values I believe would be a=1 b=-2 and c=-3.

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What is the conversion of 160g to cg??

Umnica [9.8K]

16000
is the answer
because I used the calculater

3 0

3 years ago

Trimix 10/50 is a gas mixture that contians 10% oxygen and 50% helium, and the rest is nitrogen. If a tank of trimix 10/50 has a

Marat540 [252]

Answer : The partial pressure of helium is, $1.815\times 10^4KPa$

Solution : Given,

Molar mass of $O_2$ = 32 g/mole

Molar mass of helium = 4 g/mole

Molar mass of $N_2$ = 28 g/mole

Total pressure of gas = $2.07\times 10^4KPa$

As we are given gases in percent, that means 10 g of oxygen gas, 50 g of helium gas and 40 g of nitrogen gas present in 100 g of mixture.

First we have to calculate the moles of oxygen, helium and nitrogen gas.

$\text{Moles of }O_2=\frac{\text{Mass of }O_2}{\text{Molar mass of }O_2}=\frac{10g}{32g/mole}=0.3125moles$

$\text{Moles of }He=\frac{\text{Mass of }He}{\text{Molar mass of }He}=\frac{50g}{4g/mole}=12.5moles$

$\text{Moles of }N_2=\frac{\text{Mass of }N_2}{\text{Molar mass of }N_2}=\frac{40g}{28g/mole}=1.428moles$

Now we have to calculate the total number of moles of gas mixture.

$\text{Total number of moles of gas}=\text{Moles of oxygen gas}+\text{Mole of helium gas}+\text{Moles of nitrogen gas}$

$\text{Total number of moles of gas}=0.3125+12.5+1.428=14.24moles$

Now we have to calculate the moles fraction of helium gas.

$\text{Mole fraction of He gas}=\frac{\text{Moles of He gas}}{\text{Total number of moles of gas}}=\frac{12.5}{14.25}=0.877$

Now we have to calculate the partial pressure of helium.

$p_{He}=X_{He}\times P_T$

where,

$p_{He}$ = partial pressure of helium

$P_T$ = total pressure

$X_{He}$ = mole fraction of helium

Now put all the given values in this formula, we get

$p_{He}=(0.877)\times (2.07\times 10^4KPa)=1.815\times 10^4KPa$

Therefore, the partial pressure of helium is, $1.815\times 10^4KPa$

8 0

3 years ago

Digestion is the process of breaking down food into substances that the can use. Which of the following is a physical change tha

Yuri [45]

C - Enzymes help break down carbohydrates.

8 0

3 years ago

Read 2 more answers

. Consider the following half-reactions:

Vedmedyk [2.9K]

d. Fe(s) and Al(s)

<h3>Further explanation</h3>

In the redox reaction, it is also known

Reducing agents are substances that experience oxidation

Oxidizing agents are substances that experience reduction

The metal activity series is expressed in voltaic series

<em>Li-K-Ba-Ca-Na-Mg-Al-Mn- (H2O) -Zn-Cr-Fe-Cd-Co-Ni-Sn-Pb- (H) -Cu-Hg-Ag-Pt-Au </em>

The more to the left, the metal is more reactive (easily release electrons) and the stronger reducing agent

The more to the right, the metal is less reactive (harder to release electrons) and the stronger oxidizing agent

So that the metal located on the left can push the metal on the right in the redox reaction

The electrodes which are easier to reduce than hydrogen (H), have E cells = +

The electrodes which are easier to oxidize than hydrogen have a sign E cell = -

So the above metals or metal ions will reduce Pb²⁺ (aq) will be located to the left of the Pb in the voltaic series or which have a more negative E cell value (greater reduction power)

The metal : d. Fe(s) and Al(s)

7 0

3 years ago

Which of the following is used as a refrigerant?<br> methane<br> esters<br> freon<br> fluorine

zepelin [54]

Answer: I believe the answer would be methane

Explanation:

Hope this helps

6 0

3 years ago