I need all the answers number 13-25

A compunds whose empirical formula is xf3 consists of 65% f by mass. what is the atomic mass of x

Reika [66]

Empirical formula of compound is XF3

Compound consist of 65% F

In 100g of compound there is 65 g of F

= 65 / 19 moles of Fluorine = 3.421 moles

So moles of X = 3.421 / 3 = 1.140 moles

And in 100 g X consist of 35 g

So the molar mass of X = 35 / 1.140 = 30.71 g = 31 approximately

And it is the mass of phosphorus

So the empirical formula for the compound is PX3

4 0

4 years ago

Read 2 more answers

Two objects gravitationally attract with a force of 100 N. If the mass of one object is doubled and the mass of the other object

barxatty [35]

Hello!

Recall the equation for gravitational force:
$F_g = \frac{Gm_1m_2}{r^2}$

Fg = Force of gravity (N)
G = Gravitational constant

m1, m2 = masses of objects (kg)
r = distance between the objects' center of masses (m)

There is a DIRECT relationship between mass and gravitational force.

We are given:
$F_g = 100N$

If we were to double one mass and triple another, according to the equation:
$F'_g = \frac{G(2m_1)(3m_2)}{r^2} = 6(\frac{G(m_1)(m_2)}{r^2}) = 6F_g$

Thus:
$6 * F_g = 6 * 100 = \boxed{600N}$

5 0

3 years ago

• How does AC work?

Juli2301 [7.4K]

AC reverses the current in periods, and the current flows in 2 directions.
DC only flows in one direction and is constant.

AC is typically used to transfer power over long distances from a generator to your home, stepping it up after it's generated to send it over the distance, then stepping it back down so that it is usable in your home.

DC is used typically inside of devices, as it sends a certain amount of electricity through the wires.

Nicolas Tesla, was ripped off by Edison to replace his DC stations with AC instead. ^^

4 0

3 years ago

How many "one-sixth parts are needed to make one<br>whole?

TEA [102]

6 one-sixth parts are needed to make a whole.

8 0

4 years ago

A voltmeter with resistance RV is connected across the terminals of a battery of emf and internal resistance r. Find the potenti

makvit [3.9K]

Answer:

voltage measured by the voltmeter = (E × RV)/(r + RV)

Explanation:

The circuit diagram for this description is presented in the attached image.

The internal resistance of an emf source is modelled to be in series with the source.

Therefore, the end product is a circuit with the battery in series connection with the internal resistance and resistance of the volunteer. The voltage picked up by the volunteer is the voltage across resistor RV.

Total resistance in the circuit = (r + RV) ohms (since both resistors are in parallel)

Current produced by the emf source = E/(Total resistance) = E/(r + RV)

The voltage across resistor RV = current flowing through this resistor × its resistance.

Since all the circuit elements are in series with each other, same current, E/(r + RV) flows through them all

Voltage across RV = voltage measured by the voltmeter = [E/(r + RV)] × RV = (E × RV)/(r + RV) = (E.RV)/(r + RV)

4 0

3 years ago