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2 years ago

Describe the chemical calcium-oxide.

Chemistry

1 answer:

timama [110]2 years ago

5 0

Answer:

Explanation:

Mallabone’s tests suggest there’s no risk the jacket liner will explode or heat up so much that it risks causing burns. The reaction also doesn’t produce acidic byproducts. And because calcium oxide doesn’t react with humidity (water vapor in the air), the liners can be stored for long periods and still work when needed.

Calcium oxide: A substance that gives off heat as it chemically reacts with water. Its chemical formula is CaO (which means each molecule is made up of one calcium atom and one oxygen atom).

Exothermic reaction: A chemical reaction that generates heat as it proceeds. (In Greek, “exo” means outside and “therm” means heat.)

Thought this might help ;)

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How do you identify producers and consumers?

Alja [10]

Producers produce a product
Consumers buy that product

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3 years ago

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A football is inflated to 12psi at 20°C What is the new pressure in the football

Radda [10]

Answer: The new pressure is 3 psi.

Explanation:

Given: $P_{1}$ = 12 psi, $T_{1} = 20^{o}C$

$P_{2}$ = ?, $T_{2} = 5^{o}C$

Formula used is as follows.

$\frac{P_{1}}{T_{1}} = \frac{P_{2}}{T_{2}}\\\frac{12 psi}{20^{o}C} = \frac{P_{2}}{5^{o}C}\\P_{2} = \frac{12 psi \times 5^{o}C}{20^{o}C}\\= 3 psi$

Thus, we can conclude that the new pressure is 3 psi.

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3 years ago

2.4 g of a solid is added to 91 g of water. What is the mass % concentration of the solution?

vladimir2022 [97]

Answer:

2.64%

Explanation:

mass percent = (grams of solute / grams of solution) x 100

mass percent = (2.4 / 91) × 100

mass percent = 2.64% to 3sf

8 0

1 year ago

What is the kinetic energy of the emitted electrons when cesium is exposed to UV rays of frequency 1.0×1015Hz?

RideAnS [48]

The kinetic energy of the emitted electrons of cesium when it is exposed to UV rays of frequency $1.0 \times {10^{15}}\;{\text{Hz}}$ is $\boxed{6.63 \times {{10}^{ - 19}}\;{\text{J}}}$

Further Explanation:

Photoelectric effect:

When light is made to fall on any substance, electrons are emitted from it. This is known as the photoelectric effect and the emitted electrons are called photoelectrons. The electrons are emitted because of the transference of energy from light to the electrons.

Cesium is a member of the alkali metal group so it is highly reactive and shows photoelectric effect to the maximum extent. It can remove its electron so easily because of its atomic size. Due to large atomic size of cesium, its outermost electrons are held very less tightly to the nucleus and therefore removed easily.

According to the Planck-Einstein equation, the energy is proportional to the frequency and is expressed as follows:

${\mathbf{E=h\nu }}$ ......(1)

Here,

${\text{E}}$ is the energy.

$h$ is the Plank’s constant.

$\nu$ is the frequency.

The frequency of UV rays is $1.0 \times {10^{15}}\;{\text{Hz}}$ or $1.0 \times {10^{15}}\;{{\text{s}}^{ - 1}}$

The value of Planck’s constant is $6.626 \times {10^{ - 34}}\;{\text{J}}\cdot{\text{s}}$ .

Substitute these values in equation (1)

$\begin{aligned}{\text{E}}&=\left( {6.626 \times {{10}^{ - 34}}\;{\text{J}}\cdot{\text{s}}}\right)\left( {1.0 \times {{10}^{15}}\;{{\text{s}}^{ - 1}}}\right)\\&=6.63\times {10^{ - 19}}\;{\text{J}}\\\end{aligned}$

But when electrons are ejected out from the surface of the substance, all of its energy is considered as kinetic energy.

So the kinetic energy of the electrons is ${\mathbf{6}}{\mathbf{.63 \times 1}}{{\mathbf{0}}^{{\mathbf{ - 19}}}}\;{\mathbf{J}}$ .

Learn more:

1. Statement about subatomic particle: brainly.com/question/3176193

2. The energy of a photon in light: brainly.com/question/7590814

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Structure of the atom

Keywords: kinetic energy, frequency, energy, photoelectric effect, Planck's constant, light, electrons, photoelectrons, proportional, transference, reactive, cesium.

7 0

3 years ago

Read 2 more answers

The chemical equation below is correctly balanced.

DIA [1.3K]

Answer:

44.8 L of O2 will react (option D)

Explanation:

Step 1: Data given

Number of moles of SO2 = 4.00 moles

STP = Pressure = 1 atm and temperature = 273 K

Step 2: The balanced equation

2 SO2(g) + O2(g) → 2 SO3(g)

Step 3: Calculate moles of O2

For 2 moles SO2, we need 1 mol O2 to produce 2 moles SO3

For 4.00 moles SO2 we need 4.00 / 2 = 2.00 moles O2

Step 4: Calculate volume of O2

For 1 mol we have a volume of 22.4 L

V = (n*R*T)/ p

V = (2.00 * 0.08206 * 273)/p

V = 44.8 L

For 2.00 moles we have a volume of 2*22.4 = 44.8 L

44.8 L of O2 will react (option D)

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3 years ago