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3 years ago

How many total atoms are in 0.250 g of p2o5?

2 answers:

5 0

There are 2 P atoms and 5 O atoms which results in a total of 7 atoms per molecule. Hope this helps you out; I had the same question yesterday on my 9th grade Physical Science test.

Strike441 [17]3 years ago

3 0

Answer:

3.71 × 10²¹ atoms

Explanation:

The molar mass of P₂O₅ is 283.89 g/mol. The moles of P₂O₅ corresponding to 0.250 g of P₂O₅ are:

0.250 g × (1 mol/283.89 g) = 8.81 × 10⁻⁴ mol

In 1 mole of P₂O₅ there are 6.02 × 10²³ molecules of P₂O₅ (Avogadro's number). In 8.81 × 10⁻⁴ moles of P₂O₅, the molecules of P₂O₅ are:

8.81 × 10⁻⁴ mol × (6.02 × 10²³ molecule/ 1 mol) = 5.30 × 10²⁰ molecule

In 1 molecule of P₂O₅, there are 7 atoms (2 atoms of P and 5 atoms of O). In 5.30 × 10²⁰ molecules of P₂O₅, the number of atoms is:

5.30 × 10²⁰ molecule × (7 atom/1 molecule) = 3.71 × 10²¹ atom

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Which equation below represents a generic equation suggested by a graph showing a hyperbola?

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Answer:

y = k/x

Explanation:

y = k/x is a graph of a hyperbola that has been rotated about the origin.

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3 years ago

If you heat a fixed quantity of gas, which of the following statements are true?Check all that apply.a.The volume will always in

kherson [118]

Answer:

Explanation:

Given

there is fix Quantity of gas i.e. mass of gas is constant

From ideal gas Equation

PV=nRT

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(c)true , Product of Pressure and volume depends upon temperature thus it also increases with temperature.

(d)Density of gas may or may not increases

As density is $\frac{mass}{volume}$

volume may increase or decrease as temperature increase .

(e)false

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3 years ago

The catapults on the uss george h.w. bush can launch aircraft from rest to a speed of 150 mph over a distance of 270 feet. find

vlabodo [156]

Hope this helps, have a great day ahead!

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3 years ago

The momentum of a falling rock is found to be 200 kg m/s. What is the mass of the rock if it falls with a velocity of 5.0 m/s

Snezhnost [94]

Answer:

$\boxed {\boxed {\sf 40 \ kilograms}}$

Explanation:

Momentum is the product of velocity and mass. The formula is:

$p=m*v$

We know the rock is falling. Its momentum is 200 kilograms meters per second and its velocity is 5 meters per second. Substitute the values into the formula.

$200 \ kg \ m/s = m * 5.0 \ m/s$

We are solving for m, the mass. We must isolate the variable. It is being multiplied by 5 meters per second. The inverse of multiplication is division, so we divided both sides by 5.0 m/s.

$\frac{200 \ kg \ m/s}{5.0 \ m/s}=\frac{ m* 5.0 \ m/s }{5.0 \ m/s}$

$\frac{200 \ kg \ m/s}{5.0 \ m/s}=m$

The units of meters per second (m/s) cancel.

$\frac{200 \ kg}{5.0 } =m$

$40 \ kg = m$

The falling rock has a mass of 40 kilograms.

4 0

3 years ago

An athlete at the gym holds a 3.0 kg steel ball in his hand. His arm is 60 cm long and has a mass of 3.8 kg, with the center of

Serggg [28]

Answer:

(a) τ = 26.58 Nm

(b) τ = 18.79 Nm

Explanation:

(a)

First we find the torque due to the ball in hand:

τ₁ = F₁d₁

where,

τ₁ = Torque due to ball in hand = ?

F₁ = Force due to ball in hand = m₁g = (3 kg)(9.8 m/s²) = 29.4 N

d₁ = perpendicular distance between ball and shoulder = 60 cm = 0.6 m

τ₁ = (29.4 N)(0.6 m)

τ₁ = 17.64 Nm

Now, we calculate the torque due to the his arm:

τ₁ = F₁d₁

where,

τ₂ = Torque due to arm = ?

F₂ = Force due to arm = m₂g = (3.8 kg)(9.8 m/s²) = 37.24 N

d₂ = perpendicular distance between center of mass and shoulder = 40% of 60 cm = (0.4)(60 cm) = 24 cm = 0.24 m

τ₂ = (37.24 N)(0.24 m)

τ₂ = 8.94 Nm

Since, both torques have same direction. Therefore, total torque will be:

τ = τ₁ + τ₂

τ = 17.64 Nm + 8.94 Nm

τ = 26.58 Nm

(b)

Now, the arm is at 45° below horizontal line.

First we find the torque due to the ball in hand:

τ₁ = F₁d₁

where,

τ₁ = Torque due to ball in hand = ?

F₁ = Force due to ball in hand = m₁g = (3 kg)(9.8 m/s²) = 29.4 N

42.42 cm = 0.4242 m

τ₁ = (29.4 N)(0.4242 m)

τ₁ = 12.47 Nm

Now, we calculate the torque due to the his arm:

τ₁ = F₁d₁

where,

τ₂ = Torque due to arm = ?

F₂ = Force due to arm = m₂g = (3.8 kg)(9.8 m/s²) = 37.24 N

d₂ = perpendicular distance between center of mass and shoulder = 40% of (60 cm)(Cos 45°) = (0.4)(42.42 cm) = 16.96 cm = 0.1696 m

τ₂ = (37.24 N)(0.1696 m)

τ₂ = 6.32 Nm

Since, both torques have same direction. Therefore, total torque will be:

τ = τ₁ + τ₂

τ = 12.47 Nm + 6.32 Nm

τ = 18.79 Nm

3 0

3 years ago