Is your breath becoming visible on a cold day a physical change

Answer:

See explanation

Explanation:

The reaction between alcohol and acidified potassium dichromate  is a redox reaction. This reaction can be used to detect a drunken driver.

Alcohols can be oxidized to aldehydes, ketones and carboxylic acids depending on the structure of the alcohol. Primary alcohols yield adehydes and carboxylic acids while secondary alcohols are oxidized to ketones.

The colour of the acidified potassium dichromate turns from orange to green when exposed to alcohols from the breath of a drunken driver.

Answer:

Salinity is a measure of the 'saltiness' of seawater, or more precisely the amount of dissolved matter within seawater.

Explanation:

alto cumulus is the pic

The wavelength of the radiation : λ=5.792 x 10⁻⁸ m = 5.792 x 10⁻⁶ cm

Region of Ultraviolet

Given

A frequency : 5.18 x10¹⁵ Hz

Required

The wavelength

Solution

Frequency (f): the number of waves per second  

Wavelength (λ): the distance from one crest/one trough to another

Fast wave propagation (v): the distance traveled by waves per unit of time  

v= 3 x 10⁸ m/s

General formula :

v = λ.f

λ=v/f

Input the value :

λ=3.10⁸ : 5.18.10¹⁵

λ=5.792 x 10⁻⁸ m = 5.792 x 10⁻⁶ cm

Region of Ultraviolet (4000 - 10 A°, 4 x 10⁻⁵ - 10⁻⁷ cm,7.5 x 10¹⁴ - 3 x 10¹⁷ Hz)

Answer:

The density (more precisely, the volumetric mass density; also known as specific mass), of a substance is its mass per unit volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although the Latin letter D can also be used.

Image 1 shows that the sun is travelling from the left while image 2 shows that the sun is travelling from the right.

We know that the solar system is composed of the sun and the planets. The planets move round the sun in concentric circles and the sun is the focus. This is the heliocentric model of the solar system.

The moon is also a part of the celestial bodies and the light from the moon is dependent on the direction of the movement of the sun. We have to recall that the moon is a non luminous object.

Learn more about the moon:https://brainly.com/question/13538936

#SPJ1

Answer:

3012.51×10²³ atoms of Ne

Explanation:

Given data:

Mass of Ne = 10090 g

Number of atoms = ?

Solution;

Formula:

Number of moles = mass/ molar mass

Molar mass of Ne = 20.17 g/mol

Number of moles = 10090 g/ 20.17 g/mol

Number of moles = 500.25 mol

Number of atoms:

1 mole contain 6.022×10²³ atoms

500.25 mol × 6.022×10²³ atoms / 1 mol

3012.51×10²³ atoms

Answer:

extensive properties such as mass and volume depend on something like perhaps the amount of what's measured. physical properties can be measured without changing substance chemical identity.

metals are the elements which exhibit degree of metallic behavior is know as metals. non metals are such elements which do not posses any metallic behavior and mekkloids are those elements that posses some of the properties like metal. but they act either like metals or non metals n they also have the same physical properties

Answer:

either first or second if not them try d but I'm pretty sure a also I'm sorry if I getbyou this wrong I dearly apologize

Balanced equation :

ScF₂ + 2KBr ⇒ 2KF + ScBr₂

Given

Reaction

ScF₂ + KBr ⇒ KF + ScBr₂

Required

Balanced equation

Solution

1. Give coefficient

ScF₂ + aKBr ⇒ bKF + cScBr₂

Sc, left=1, right=c⇒c=1

F, left=2, right=b⇒b=2

K, left=a, right=b⇒a=b⇒a=2

The equation becomes :

ScF₂ + 2KBr ⇒ 2KF + ScBr₂

Answer:

the Earth rotates on an imaginary line called its axis and different parts of the planet are facing towards the Sun or away from it. it takes 24 hours for the world to turn all the way around, and we call this a day.

Explanation:

Answer:

[tex]1.167\times 10^{-3}\ \text{mol/h}[/tex]

Explanation:

[tex]R_1[/tex] = Rate of diffusion of [tex]CO_2[/tex] = [tex]9.31\times 10^{-4}\ \text{mol/h}[/tex]

[tex]R_2[/tex] = Rate of diffusion of [tex]N_2[/tex]

[tex]M_1[/tex] = Molar mass of [tex]CO_2[/tex] = 44.01 g/mol

[tex]M_2[/tex] = Molar mass of [tex]N_2[/tex] = 28.0134 g/mol

From Graham's law we have the relation

[tex]\dfrac{R_1}{R_2}=\sqrt{\dfrac{M_2}{M_1}}\\\Rightarrow R_2=\dfrac{R_1}{\sqrt{\dfrac{M_2}{M_1}}}\\\Rightarrow R_2=\dfrac{9.31\times 10^{-4}}{\sqrt{\dfrac{28.0134}{44.01}}}\\\Rightarrow R_2=1.167\times 10^{-3}\ \text{mol/h}[/tex]

The rate of effusion of the [tex]N_2[/tex] gas would be [tex]1.167\times 10^{-3}\ \text{mol/h}[/tex].

Answer: in the daytime the sun is out so the stars are not visible becuase the suns reflection! At night When you gaze at the constellations, every star produces an image that's the same size, but your retina isn't sensitive enough to respond to the outer parts of those images except for the brighter stars — which therefore look bigger than the fainter ones.

Explanation:

This is what I found on goog.le a while ago now it might actually help if I’m wrong I apologiz, I hope this was your quistion!

Answer:

Volume of the sulfuric acid (25cm³), same mass of each metal (1g)

Explanation:

In an experiment, the CONTROL VARIABLE also known as constant is the variable that is kept unchanged for all groups in an experiment. This is done in order not to influence the outcome of the experiment.

In this case, students are trying to investigate the reactivity of four different metals. They added 1 g of each metal to 25cm³ of sulfuric acid and recorded the temperature change. Based on the explanation of control variable above, the VOLUME OF SULFURIC ACID (25cm³) and the MASS OF EACH METAL (1g) are the CONTROL VARIABLES because they are the same or unchanged in this experiment.

Answer: The pressure of the gas is 0.34 atm

Explanation:

According to ideal gas equation:

[tex]PV=nRT[/tex]

P = pressure of gas = ?

V = Volume of gas = 605 ml = 0.605 L      (1L=1000ml)

n = number of moles  = 0.00803

R = gas constant =[tex]0.0821Latm/Kmol[/tex]

T =temperature =[tex]39^0C=(39+273)K=312K[/tex]

[tex]P=\frac{nRT}{V}[/tex]

[tex]P=\frac{0.00803\times 0.0821 L atm/K mol\times 312K}{0.605L}=0.34atm[/tex]

The pressure of the gas is 0.34 atm

Answer:

0.034 Liters

Explanation:

Answer:

Molar mass: 399.9 g/mol

The mass of iron(III) sulfate is 269 grams.

Explanation:

First of all, you have to find the molar mass of Fe2(SO4)3.

So you find the molar first for each element

However, there are 2 iron atoms, 3 sulfur atoms, and 12 oxygen atoms.(Don't forget the 3 outside the parenthesis of SO4).

So you do this

So the final answer is 399.9 g/mol

Second of all, if you want to find the mass of Fe2(SO4)3, you have to convert from formula units to moles. After that, then you convert from moles to grams.

If you want to convert from molecules to molecules, you have to use Avogadro's number. Avogadro's number is 6.02 x 10^23. Then if you want to convert from moles to grams, you use the molar mass. We already know that the molar mass is 399.9 g/mol.

Therefore, now use dimensional analysis to show your work.

Formula units in the beginning and the moles will cancel out.

But we need to use significant figures with the least digits(which is 4.05) So we round to the nearest whole number.

So the final answer for the mass of iron(III) sulfate is 269 grams(don't forget the units).

Hope it helped!

Answer:

Answer:

B.) conclusion

Answer:

Explanation:

The major regulation, regulatory, and communicating system in the body is the nervous system. It is the foundation of all mental operation, including thinking, learning, and memory. The nervous system, along with the endocrine system, is responsible for controlling and sustaining homeostasis.

Answer:

3 atoms of O

8.57g

Explanation:

The problem here is to find the mass of oxygen in the compound and the number of atoms of oxygen.

 The formula of the compound is:

 NaHCO₃;

   Here we have:

      1 atom of Na

     1 atom of H

     1 atom of C

     3 atoms of O

So there are 3 atoms of O

To find the mass of oxygen , we use the molar mass of oxygen;

     Molar mass of oxygen  = 16g/mol

 Mass of oxygen  = [tex]\frac{3(16)}{84.01}[/tex]  x 15  = 8.57g

Answer:

it is option c liner eclipse

Answer:

A-It is a lunar eclipse, in which the Earth casts a shadow on the Moon.

Answer:

To ensure that everyone enjoys using your pool, it is important to keep the swimming pool pH levels in balance at all times. If the pH is too high, it could cause skin irritation and corrode metal parts on the pool. If the pH is too low, it could create a situation where the chlorine in the pool isn't as effective.

Explanation:

Answer:

I don't see multiple choice, so I'll answer this based on what I have learned on my free time.

Explanation:

Usually, when a ton of Urine is in a pool, it can throw off the Ph balance, and can even damage human eyes. Trust me, it's happened to me one time. my eyes burned like fire.

It would be Ionic Compounds.