What do these two changes have in common?
using a large magnet to remove pieces of iron from a junkyard
rain forming in a cloud
Select all that apply.
Both are caused by heating.
Both are only physical changes.
Both conserve mass.
Both are chemical changes.

Answer:

The absolute uncertainty is approximately 1.69 × 10⁻³

Explanation:

The volume needed for NaOH needed to make the solution = 16.66 ml

The wt% of the added NaOH = 53.4 wt%

The volume of the NaOH to be prepared = 2.00 L

The concentration of the NaOH to be prepared = 0.169 M

The molar mass of NaOH = 39.997 g/mol

Therefore, 100 g of sample contains 53.4 g of NaOH

The mass of the sample = 16.66 × 1.52 = 25.3232 g

The mass of NaOH in the sample = 0.534 × 25.3232 = 13.5225888 g ≈ 13.52 g

Therefore;

The number of moles of NaOH = 13.52/39.9971 = 0.3381 moles

Therefore, we have 0.3381 moles in 2.00L solution, which gives;

The number of moles per liter = 0.3881/2 = 0.169045 moles/liter

The molarity ≈ 0.169 M

The absolute uncertainty, u(c) is given as follows;

[tex]u(c) = \sqrt{ \left (\dfrac{0.01}{16.66} \right )^2 + \left ( \dfrac{0.4}{53.4} \right )^2 + \left ( \dfrac{0.01}{1.52} \right )^2 } \times 0.169 \approx 1.69 \times 10^{-3}[/tex]

The absolute uncertainty, u(c) ≈ 1.69 × 10⁻³.

Answer:

Explanation:

A balloon if fully inflated and then placed close to a hot place is likely to blow. This would result from the increased air pressure inside the balloon. Increase in temperature leads to an increase in the energy of the air molecules which move at a higher speed and more collisions.May 11, 2018

Answer: Here you go

Explanation:

The general equation for an exothermic reaction is: Reactants → Products + Energy.

Answer:

28.00 g is the answer

Answer:200

Explanation:

It’s is the answer

Answer:

Follows are the solution:

Explanation:

A + B = C

Its response decreases over time as well as consumption of a reactants.  

r = -kAB

during response A convert into 2x while B convert into x to form 3x of C

let's  y = C

y = 3x

Still not converted sum of reaction  

for A: 100 - 2x

for B: 50 - x

Shift of x over time  

[tex]\frac{dx}{dt} = \frac{-k(100 - 2x)}{(50 - x)}[/tex]

Integration of x as regards t  

[tex]\frac{1}{[(100 - 2x)(50 - x)]} dx = -k dt\\\\\frac{1}{2[(50 - x)(50 - x)]} dx = -k dt\\\\\ integral\ \frac{1}{2[(50 - x)^2]} dx =\ integral [-k ] \ dt\\\\\frac{-1}{[100-2x]} = -kt + D \\\\[/tex]

D is the constant of integration

initial conditions: t = 0, x = 0

[tex]\frac{-1}{[100-2x]} = -kt + D \\\\\frac{ -1}{[100]} = 0 + D\\\\D= \frac{-1}{100}\\\\[/tex]

hence we get:

[tex]\frac{-1}{[100-2x]}= -kt -\frac{1}{100}\\\\or \\\\ \frac{1}{(100-2x)} = kt + \frac{1}{100}[/tex]

after t = 7 minutes , [tex]C = 10 \ g = 3x[/tex]

[tex]3x = 10\\\\x = \frac{10}{3}[/tex]

Insert the above value x into [tex]\frac{1}{(100-2x)}[/tex] equation [tex]= kt + \frac{1}{100}[/tex] to get k.  

[tex]\to \frac{1}{(100-2\times \frac{10}{3})} = k \times (7) + \frac{1}{100} \\\\ \to \frac{1}{(100- 2 \times 3.33)} = \frac{700k + 1}{100} \\\\ \to \frac{1}{(100-6.66)} = \frac{700k + 1}{100}\\\\ \to \frac{1}{93.34} = \frac{700k + 1}{100} \\\\[/tex]

[tex]\to 100 = 93.34(700k + 1) \\\\ \to 100 = 65,338k + 700 \\\\ \to 65,338k = -600 \\\\ \to k = \frac{-600}{ 65,338} \\\\ \to k= - 0.0091[/tex]

therefore plugging in the equation the above value of k  

[tex]\to \frac{1}{(100-2x)} = kt +\frac{1}{100} \\\\\to \frac{1}{(100-2x)} = -0.0091t + \frac{1}{100}\\\\\to \frac{1}{(100-2x)} = \frac{1 -0.91t}{100}\\\\\to \frac{1}{2(50-x)} = \frac{1 -0.91t}{100}\\\\\to \frac{1}{(50-x)} = \frac{1 -0.91t}{50}\\\\\to 50= (1-0.91t)(50-x)\\\\\to 50 = 50-45.5t-x-0.91tx\\\\\to x+0.91xt= -45.5t\\\\\to x(1+0.91t)= -45.5t\\\\\to x=\frac{-45.5t}{1+0.91t}[/tex]

Let y = C

, calculate C:

y = 3x

[tex]y =3 \times \frac{-45.5t}{1+0.91t}[/tex]

amount of C formed in 28 mins

[tex]x = \frac{-45.5t}{1+0.91t} ,[/tex] plug t = 28

[tex]\to x = \frac{-1274}{1+25.48} \\\\\to x = \frac{-1274}{26.48} \\\\\to x= -48.26[/tex]

therefore amount of C formed in 28 minutes is = 3x = 144.78 grams

C: [tex]y =3 \times \frac{-45.5t}{1+0.91t}[/tex]

y= 136.5 =137

Answer:

seeds are protected in fruits in such kind of plants.

Explanation:

The flowering plants are also known as Angiospermae, or Magnoliophyta. Flowering plants are plants that grow flowers. Such plants use seeds to reproduce, or make more plants like them.

Seeds are protected in fruits in such kinds of plants.

Examples of flowering plants are daisies, tulips, oaks, apples.

Answer:

Seeds are protected by a fruit

Explanation:

Answer:

the nucleus, the coma, the ion tail, and the dust tail

Explanation:

A comet is made up of four visible parts: the nucleus, the coma, the ion tail, and the dust tail. The nucleus is a solid body typically a few kilometres in diameter and made up of a mixture of volatile ices (predominantly water ice) and silicate and organic dust particles.

Answer:

calcium.

Explanation:

because of

thanks

Answer:

[tex]\frac{3}{2}[/tex]

Explanation:

No of moles : [tex]\frac{given mass}{atomic mass}[/tex]

so the given mass is 42 gm and atomic mass of silicon is 24 when u solve it u get 3/2

Answer:

The answer is A. Test Tube of zinc oxide

The indivisibility of an atom was proved wrong: an atom can be further subdivided into protons, neutrons and electrons. ... According to Dalton, the atoms of same element are similar in all respects. However, atoms of some elements vary in their masses and densities. These atoms of different masses are called isotopes.

volume of ozone : 19.15 ml

Graham's law: the rate of effusion of a gas is inversely proportional to the square root of its molar masses or

[tex]\tt \dfrac{r_{CO_2}}{r_{O_3}}=\dfrac{\sqrt{M_{O_3}} }{\sqrt{M_{CO_2}}} }[/tex]

rate of CO₂  , M CO₂ = 44,01 g/mol

[tex]\tt r~CO_2=\dfrac{20~ml}{100~s}[/tex]

[tex]\tt r~O_3=\dfrac{x}{100~s}[/tex]

volume of ozone

[tex]\tt \dfrac{r~{CO_2}}{r~O_3}=\dfrac{\sqrt{48} }{\sqrt{44.01} }\\\\\dfrac{20}{x}=\dfrac{\sqrt{48} }{\sqrt{44.01} }\\\\x=\dfrac{20.\sqrt{44.01} }{\sqrt{48} }=19.15~ml[/tex]

Answer:

The particles in a gas are moving very quickly in random directions.

The particles in a solid are tightly packed and locked in place, and they are vibrating in their place.

The particles in a liquid are close together (touching) but they are able to move/slide/flow past each other.

brainliet please?

x

Answer: Gases expand to fill their containers, have a fluid nature, low density, can be compressed, diffuse and effuse - move in small hole spray perfume .

Explanation:

Gases have such an unpredictable nature like fluid, very low density, can be condensed, disperse and effuse move in tiny hole spray fragrance, and they dominate far more room than the fine solids out of which they establish. 

Because gases are harder to identify directly, gases are defined using four physical qualities or observable characteristics such as temperature, density, particles number, and volatility.

Learn more:

https://brainly.com/question/1369730?referrer=searchResults

Answer:

london I'm not dead -yet-

Explanation:

thank u for being there for me when no one else was

btw she visited me last night "I made sure to punch her in da nose but my fist hit the wall instead of her face so yea funnn" good luck in this life

Answer: YEAH ITS the third one

Explanation: duhh

Answer:

Candle wax will melt to a liquid and burn as a gas. Only covalent compounds can be liquid or gas!

Explanation:

Question: Is Wax Ionic Or Covalent? - Ceramicsexpandusceramics.com

In the given question, wax is a covalent compound because it is composed of nonmetal atoms that share electrons to create covalent bonds.

Covalent compounds are formed when two or more nonmetal atoms share electrons in order to achieve a stable electron configuration.

Therefore, wax is a covalent compound because it is made up of non-metal atoms sharing electrons to form covalent bonds.

Learn more about covalent compounds here:

https://brainly.com/question/11632372

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Answer:

Try magnitude.

Explanation:

Answer:

The Richter scale measures the largest wiggle (amplitude)

Explanation:

The Richter scale measures the largest wiggle (amplitude) on the recording, but other magnitude scales measure different parts of the earthquake. ... Intensity is a measure of the shaking and damage caused by the earthquake; this value changes from location to location.

Given problem:

    S₂O₈²⁻

Find the oxidation number of S;

Oxidation number presents the extent of oxidation of each atom of elements a molecular formular or formula unit or an ionic radical.

  For radicals:

          "the algebraic sum of all the oxidation numbers of all atoms in an ion containing more than one kind of atom is equal to the charge on the ion  "

 S₂O₈²⁻;   oxidation number of O is usually -2

             2(S) + 8(-2) = -2

               2S - 16  = -2

               2S = -2 + 16

                2S  = 14

                   S  = +7

The oxidation state of S in the radical is +7

Answer:

the seven most abundant elements are

oxygen

carbon

hydrogen

nitrogen

calcium

phosphorus

Explanation:

hope this helps

good luck:)

Answer:

oxygen

carbon

hydrogen

nitrogen

calcium

phosphorus

Answer: Explanation:

With an increase in temperature, there is typically an increase in the molecular interchange as molecules move faster in higher temperatures. The gas viscosity will increase with temperature. ... With high temperatures, viscosity increases in gases and decreases in liquids, the drag force will do the same.

The increase in temperature causes the kinetic or thermal energy to increase and the molecules become more mobile. The attractive binding energy is reduced and therefore the viscosity is reduced.

liquids show a reduction in viscosity with increasing temperature. With high temperatures, viscosity increases in gases and decreases in liquids, the drag force will do the same.

Answer: A Meteor

Explanation:

A streak of light in the sky and says she is seeing a shooting star. She's most likely observing is a meteor. Therefore, option C is correct.

A meteor is an object from space or a meteoroid that touches down on Earth. The air on the space rock creates drag that causes it to become incredibly heated as it falls toward Earth.

When the earth travels through cometary debris during its orbit around the Sun, meteor showers will result. Although the Earth's orbit around the Sun is nearly round, the majority of comets have very elliptical orbits.

A meteoroid becomes a meteor, or a streak of light in the sky, if it gets close enough to Earth and enters its atmosphere. These light striations are sometimes referred to as "shooting stars" due to their appearance. However, stars are not what meteors are.

Thus, option C is correct.

To learn more about meteor, follow the link;

https://brainly.com/question/11504264

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Answer:

At sea level, or at zero feet in altitude, the boiling point of water is at 212 °F (100 °C). Once the water has reached this boiling point, the US Center for Disease Control recommends keeping it at a rolling boil for about a minute to make sure it is purified.

Answer:

Water boils at 212 degrees fahrenheit or 100 degree celcius

Explanation:

its true

Incomplete question. However, I provided a specific example of stewardship of the atmosphere.

Explanation:

First, note that the term stewardship refers to the belief that humans are obligated to take care and look after our environment (which includes the atmosphere.

An example of this is: deciding to change our mode of transportation: What this entails is that we may decide to switch to riding a bicycle to places rather than going by car. By so doing you will be reducing the number of greenhouse gases emitted into the environment as bicycles do not emit harmful gases when used.

Answer: Each orbital is found on different areas of the periodic table. The s sublevels are found on the first(left) and last(right) columns of the period table which hold a maximum of two electrons since it only has one orbital. First, each orbital can hold a maximum of two electrons. The other three sublevels: p, d, and f respectively have more orbitals, which is why they can hold more electrons. These sublevels of orbitals stand for sharp(s), principle(p), diffuse(d), and fundamental(f) (these are simply the categories of orbitals).

p has 3 orbitals so it can hold 6 electrons max. d has 5 orbitals so it can hold 10 electrons max. f has 7 orbitals so It can hold 14 electrons max.

Here is a picture of these orbital groups so you can understand a little better:

Answer:

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\ [/tex]

From the question

mass = 63 g

volume = 75 mL

We have

[tex]density = \frac{63}{75} = \frac{21}{25} \\ [/tex]

We have the final answer as

Hope this helps you