All categories

2 years ago

Chất tinh khiết là:

Chemistry

1 answer:

coldgirl [10]2 years ago

7 0

Answer:

The FitnessGram™ Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. [beep] A single lap should be completed each time you hear this sound. [ding] Remember to run in a straight line, and run as long as possible. The second time you fail to complete a lap before the sound, your test is over.

You might be interested in

C(s) + S8(s) → CS2(l)

Vanyuwa [196]

The balanced chemical reaction is written as:

4C(s) + S8(s) → 4CS2(l)

We are given the amount of carbon and sulfur to be used in the reaction. We need to determine first the limiting reactant to be able to solve this correctly.

7.70 g C ( 1 mol / 12.01 g) =0.64 mol C
19.7 g S8 ( 1 mol / 256.48 g) = 0.08 mol S8

The limiting reactant would be S8. We use this amount to calculate.

0.08 mol S8 ( 4 mol CS2 / 1 mol S8 ) ( 256.48 g / 1 mol ) = 78.8 g CS2

4 0

3 years ago

A graduated cylinder is filled to the 40.00-mL mark with a mineral oil. The masses of the cylinder before and after the addition

castortr0y [4]

Answer:

Firstly, Let's experiment this !

Experiment 1 :

159.446g - 124.966g = 34.48g

34.48g = The mass of Mineral oil.

The density of the mineral oil = M/V = 34.48g/40mL = 0.862g/cm³.

Experiment 2 :

124.966 + 18.173 = 143.139 = The mass of solid + cylinder.

124.966 + 50.952 = 175.918 = The mass of solid + cylinder + Mineral water.

175.918 - 143.139 = 32.779 = The mass of added mineral oil.

Explanation:

Now we have to find the volume of the added mineral oil using the density from experiment 1.

V = 32.779g/0.862g/cm³ = 38.02668213mL

Since we found the volume of the solid, we then have to subtract the added mineral oil volume from the total volume from experiment 1.

Volume of solid = 40-38.02668213 = 1.97331787mL

Density of solid = 18.713g/1.97331787mL = 9.483013499g/cm^3

1.97331787 = (4/3)(3.14)r³

1.97331787*(3/4)(3.14) = .4713338861

.4713338861 = r ³

r = 0.7782328425158433

r = 0.78

Now that's our final answer ! r = 0.78

5 0

3 years ago

Methane (CH4), ammonia (NH3), and oxygen (O2) can react to form hydrogen cyanide (HCN) and water according to this equation:

egoroff_w [7]

The grams of oxygen that are required to produce 1 mole of H₂O is 16 g ( answer B)

calculation

2 CH₄ + 2NH₃ +3 O₂ → 2HCN + 6H₂O

step 1: use the mole ratio to find moles of O₂

from equation above the mole ratio of O₂: H₂O is 3:6 therefore the moles of O₂ = 1 mole x3/6 =0.5 moles

step 2: find mass of O₂

mass= moles x molar mass

from periodic table the molar mass of O₂ = 16 x2= 32 g/mol

mass O₂ = 0.5 moles x 32 g/mol = 16 g (answer B)

6 0

3 years ago

Read 2 more answers

Need ASAP will give brainlist

Leokris [45]

Answer:

The answer is A :)

7 0

2 years ago

What material beats and lets you get though all of earth’s layers?

Goryan [66]

Seismic waves

Explanation:

Seismic waves are disturbances that transmits energy elastically and let's scientist have a glimpse of the interior of the earth.

These waves can pass through any component layer of the earth due to their unique properties.

There are four types of seismic waves but the two body waves are the most important in studying the earth's interior.

Seismic p-waves can pass through any earth materials as they are longitudinal waves.
Seismic s-waves are shear waves and can only pass through solids. liquids and gases cannot be sheared.

learn more:

Seismograph brainly.com/question/11292835

#learnwithBrainly

6 0

3 years ago