I need help on this question

Answer:

n = 0.19 mol

Explanation:

Given mass = 15 g

The molar mass of AsH₃ = 77.94 g/mol

We need to find the number of moles in 15 g of AsH₃. We know that,

No. of moles = given mass/molar mass

[tex]n=\dfrac{15}{77.94 }\\\\n=0.19\ mol[/tex]

So, there are 0.19 g/mol. Hence, the correct option is equal to 0.19 mol.

Answer:

Option C

Explanation:

No. of Molecules=(Given Weight/Molar weight)*Avagadro No.

Given weight of H2O=3.01g

Molar weight of H2O=18g

On applying the formula, we get:

No. of Molecules=(3.01/18)*6.023*10²³=1.01*10²³

Answer:

D

Explanation:

Answer:

In a titration, you determine an unknown concentration of a sample by adding a second reactant of known concentration. In many titrations, you use a chemical called an indicator, which lets you know when the titration finishes.

Explanation:

Answer:

The answer of this question is A

Answer: B is the right

Explanation:

Answer:

5

Explanation:

Na, N, O, O, O

Explanation:

List of All Elements That Are Nonmetals

Hydrogen (sometimes)

Carbon.

Nitrogen.

Oxygen.

Phosphorus.

Sulfur.

Metals:-

Gold.

Silver.

Iron.

Copper.

Nickel.

Aluminum.

Mercury( Liquid metal)

Titanium.

Fluorine.

Answer:

16 atm

Explanation:

Answer:

1. single replacement

Explanation:

Single replacement can be represented by AB+C ⇄B+AC, which matches the picture

Double replacement and double displacement are the same kind of reaction and can be represented by AB+CD ⇄BD+AC

Decomposition reaction can be represented by AB ⇄A+B

Answer:

while atoms form together, they percentage their outermost electrons to create more sustainable strength states. This sharing bonds the atoms into an ionic shape or a molecule

Explanation:

i hope this help a little

Answer: it think the answer is c.) The cell gets help from white blood cells or b.) The cell gets help from its neighbor cells.

Explanation:

Answer:

it produces no air pollution

Answer:

A

Explanation:

the boat does not have a force to counter act the boys it must give which means it moves cause it is one something that is not as dense as the boy (I THINK)

Explanation:

fgIf the piston moves so as to increase the pressure of the gas to 2.94 atm, ... new volume of the cylinder? ... A gas has a pressure of 699.0 mm Hg at 40.0°C. What is the temperature (in C) ...

Answer:

The reaction is exothermic as the solution becomes warm.

Explanation:

Hello there!

In this case according to the described reaction between sodium metal and water, we can write up the chemical equation whereas the products turn out to be sodium hydroxide and hydrogen gas:

[tex]2Na+2H_2O\rightarrow 2NaOH+H_2[/tex]

Moreover, these reactions are known to be highly exothermic, for that reason the solution becomes warm as the reaction releases heat as it goes to completion.

Best regards!

Answer:

Explanation:

The force acting on an object given it's mass and acceleration can be found by using the formula

force = mass × acceleration

From the question we have

net force = 2400 × 3.6

We have the final answer as

Hope this helps you

Answer:

C. one star

Explanation:

Of course our solar system has one unique star which is the sun while others have atleast two which are called binary solar

Answer:

A, C, D

Explanation:

Recall the heat capacity equation:

q = mc∆T

We're given mass, specific heat capacity, as well as the change in temperature. All we need to do is plug the numbers into the variables and we'll have our answer!

Although this question doesn't try to trick you, more often than not questions regarding energy change will attempt to throw you off with specific heat capacity. It's extremely important to note the units of the specific heat capacity and ensure that the numbers you use are in those units. As an example, the specific heat capacity might be given to you in J/mol*K - in this case, you'd have to do some unit conversions with your given data in order to fit all the numbers. In this question, we're given the specific heat capacity in J/gºC, so we don't need to change anything since all of our data is already in these units.

Anyways, back to the actual question:

q = mc∆T

q = (8.50 * [tex]10^{2}[/tex]) * (0.900) * (94.6 - 22.8)

q = 54927 (J)

Remeber to include significant figures:

54927 = 5.49 * 10^4 (J)

The required energy is 5.49 * [tex]10^{4}[/tex] Joules, or 5.49 * [tex]10^{1}[/tex] kJ

Let me know if you need any of my work to be explained!

- Breezeツ

Answer:

c

Explanation:

1. litmus paper is used when showing a change between a greater range in ph levels - so A and D are automatically a no.

2. methyl red is used to show a range in ph levels between 4.8-6

3. Option C is the only one left so im going to assume its C because its definitely not A, B, or D

Answer:

By Bayer process.

Explanation:

In the Bayer process, bauxite ore is heated in a pressure vessel along with a sodium hydroxide solution (caustic soda) at a temperature of 150 to 200 °C. At these temperatures, the aluminium is dissolved as sodium aluminate (primarily [Al(OH)4]−) in an extraction process.

Answer:

a. i. 5.092 × 10²⁰ Hz ii. 588.98554 nm ii. 10667809.11 rad/m

b. i. 5.087 × 10²⁰ Hz ii. 589.58286 nm iii. 10657001.3 rad/m

Explanation:

refractive index, n = λ/λ'  where λ = wavelength in vacuum = and λ' = wavelength in air

a. For λ = 589.15788 nm,

i. Frequency,

f = c/λ where c = speed of light in vacuum = 3 × 10⁸ m/s and λ = 589.15788 nm = 589.15788 × 10⁻⁹ m

So, f = 3 × 10⁸ m/s ÷ 589.15788 × 10⁻⁹ m

= 0.005092 × 10¹⁷ /s

= 5.092 × 10²⁰ /s

= 5.092 × 10²⁰ Hz

ii. Wavelength,

Since n = λ/λ'  where λ = wavelength in vacuum = and λ' = wavelength in air

and n = 1.0002926

λ' = λ/n

= 589.15788 nm/1.0002926

= 588.98554 nm

k = 2π/λ'

= 2π/588.98554 nm

= 0.01066780911 rad/nm

= 0.01066780911 rad/nm × 10⁹ nm/1m

= 10667809.11 rad/m

b. For λ = 589.755 37 nm.,

i. Frequency,

f = c/λ where c = speed of light in vacuum = 3 × 10⁸ m/s and λ = 589.755 37 nm. = 589.755 37 × 10⁻⁹ m

So, f = 3 × 10⁸ m/s ÷ 589.755 37 × 10⁻⁹ m

= 0.005087 × 10¹⁷ /s

= 5.087 × 10²⁰ /s

= 5.087 × 10²⁰ Hz

ii. Wavelength,

Since n = λ/λ'  where λ = wavelength in vacuum = and λ' = wavelength in air

and n = 1.0002926

λ' = λ/n

= 589.755 37 nm./1.0002926

= 589.58286 nm

k = 2π/λ'

= 2π/589.58286 nm

= 0.0106570013 rad/nm

= 0.0106570013  rad/nm × 10⁹ nm/1m

= 10657001.3 rad/m

Answer:

Mass of truck = 29.62 kg (Approx.)

Explanation:

Given:

Kinetic energy = 1200 J

Speed of truck = 9 m/s

Find:

Mass

Computation:

The kinetic energy of a thing is the force that has attributable to its movement in physics.

Kinetic energy = [1/2][m][v]²

1,200 = [1/2][m][9]²

1,200 = [1/2][m][81]

Mass of truck = 29.62 kg (Approx.)

Since we have sufficient sodium fluoride (NaF), the magnesium (Mg) will be our limiting reactant, and we will use its coefficient in the balanced equation to determine our molar ratio between the product of interest which, in this case, is sodium (Na).

We are given the mass of magnesium, 23.56 grams, which we must convert to moles by dividing the mass by the molar mass of magnesium: (23.56 g)/(24.305 g/mol) = 0.9693 mol Mg.

According to the balanced equation given, the molar ratio between sodium and magnesium is 2:1. That is, for every 2 moles of Na that are produced, one mole of Mg is consumed or reacted. The upshot is that the number of moles of sodium produced will be double the number of moles of Mg reacted. Since we have 0.9693 moles of Mg available to react, we will obtain (0.9693 mol Mg)(2 mol Na/1 mol Mg) = 1.939 mol Na.

Finally, we multiply our moles of sodium by the molar mass of sodium to get the mass: (1.939 mol Na)(22.99 g/mol) = 44.57 grams Na.

So, 44.57 grams of sodium will be produced.

The answer is given to four significant figures.

Answer:

B

Explanation:

Pressure is directly proportional to temperature

Answer:

A

Explanation: 11/22

Answer:

Length of RT = 9.22 cm to the nearest hundredth

Explanation:

Considering the image up in the attachment, ΔRST is a right-angled triangle.

The length of two sides of ΔRST is given as 11cm and 6 cm. The length of the third side which is RT can be obtained using Pythagoras ' rule which says that the sum of the squares of two sides of a right-angled triangle is equal to the square of the hypotenuse.

This rule is given as: c² = b² + a² where c is the hypotenuse and a and b are the other two sides of the right-angled triangle.

In ΔRST, the length of the hypotenuse = 11 cm, the length of one of the two sides = 6cm, length of RT = x

Solving for x: (11 cm)² =  (x cm)² + (6 cm)²

(x cm)² = 121 cm² - 36 cm²

(x cm)² = 85 cm²

x cm = √85

x = 9.22 cm to the nearest hundredth

Therefore, length of RT = 9.22 cm to the nearest hundredth

Mass is an intrinsic property of matter and is measured in kilograms. The mass of a bird is a constant. A 15-gram bird is 15 grams, whether measured on the Earth, the Moon, or Mars. Weight is a measure ofthe force of gravity on a physical object and is measured in newtons.