An element is a specific type of atom (true or false)

Answer:

2 [tex]\pi[/tex] r

Explanation:

Given that:

Radius of basketball  = 9inches

Unknown:

Hoop's circumference  = ?

Solution:

To solve this problem, we use the formula for the circumference of a circle.

The shape of the hoops is circular.

 Circumference of a circle = 2 [tex]\pi[/tex] r

R is the radius of the basketball hoop

Answer:

(c) only solute present

Explanation:

In chemistry, the mole fraction, denoted by X, refers to the number of moles of a substance in a compound/mixture divided by the total number of substances in the same compound or mixture.

In this case, we can say that mole fraction represents the number of solutes to the number of solutes and solvent in the solution i.e. X = nA/nA + nB

Where; nA = number of solutes

nB = number of solvent

X = mole fraction.

Based on this analogy, When the mole fraction of solute is 1, there is only solute present. That is; X = 1 / 1 + 0

X = 1/1 = 1.

Answer:just for the ponits

Explanation:ima be a jenna

Answer:

d = 8.96 g/cm³

Explanation:

Given data:

Volume of sample = 10.0 cm³

Mass of copper = 89.6 g

Density of copper = ?

Solution:

Formula:

d = m/v

d = density

m = mass

v = volume

by putting values,

d = 89.6 g/ 10.0 cm³

d = 8.96 g/cm³

Answer:

Diaphragm controls the amount of light reaching the specimen. It is located above the condenser and below the stage. Most high quality microscopes include an Abbe condenser with an iris diaphragm. Combined, they control both the focus and quantity of light applied to the specimen.

Answer:

68.6 °C

Explanation:

From conservation of energy, the heat lost by acetone, Q = heat gained by aluminum, Q'

Q = Q'

Q = mL where Q = latent heat of vaporization of acetone, m = mass of acetone = 3.33 g and L = specific latent heat of vaporization of acetone = 518 J/g

Q' = m'c(θ₂ - θ₁) where m' = mass of aluminum = 44.0 g, c = specific heat capacity of aluminum = 0.9 J/g°C, θ₁ = initial temperature of aluminum = 25°C and θ₂ = final temperature of aluminum = unknown

So, mL = m'c(θ₂ - θ₁)

θ₂ - θ₁ = mL/m'c

θ₂ = mL/m'c + θ₁

substituting the values of the variables into the equation, we have

θ₂ = 3.33 g × 518 J/g/(44.0 g × 0.9 J/g°C) + 25 °C

θ₂ = 1724.94 J/(39.6 J/°C) + 25 °C

θ₂ = 43.56 °C + 25 °C

θ₂ = 68.56 °C

θ₂ ≅ 68.6 °C

So, the final temperature (in °C) of the metal block is 68.6 °C.

The final temperature of the metal block is 74.97°C

The specific heat of a substance is the required quantity of heat needed to raise the temperature of 1 gram of the substance by 1° C.

From the parameters given:

The number of moles of acetone is:

[tex]\mathbf{= 3.33 g \times \dfrac{mol}{58.08 \ mol}}[/tex]

= 0.0573 mol

At standard conditions, the heat of vaporization of acetone is:

[tex]\mathbf{\Delta H = 32.0 \ kJ/mol \times 0.0578 \ mol } \\ \\ \mathbf{\Delta H = 1.8496 \ kJ } \\ \\ \mathbf{ \Delta H = 1.85 \times 10^3 \ J}[/tex]

Given that:

The specific heat of the aluminum is = 0.903 J/g° C

The heat energy can be computed as:

q = msΔT

q = 41 g × 0.903 J/g° C × (x - 25°C)

Using the calorimetry principle, heat energy lost by metal = heat energy gained by acetone.

i.e.

[tex]\mathbf{q_{(acetone)} gain = q_{(metal)} lost }[/tex]

[tex]\mathbf{-1.85 \times 10^3 \ J = - 41 g \times 0.903 \ J/g^0 C \times ( x - 25^0 c) }[/tex]

[tex]\mathbf{1.85 \times 10^3 \ J = 41 g \times 0.903 \ J/g^0 C \times ( x - 25^0 c) }[/tex]

[tex]\mathbf{(x - 25 ^0 C) = \dfrac{1.85 \times 10^3 \ J }{ 41 g \times 0.903 \ J/g^0 C}}[/tex]

[tex]\mathbf{(x - 25 ^0 C) = 49.97^0 C}}[/tex]

[tex]\mathbf{x = 49.97^0 C+25 ^0 C}}[/tex]

x = 74.97 °C

Learn more about specific heat here:

https://brainly.com/question/1430612

Answer:

B. Isotopes mean having differing number of neutrons but having the same amount of protons basically.

Explanation:

B. The atoms are isotopes of each other

Given

The first atom : 8 protons, 8 neutrons and 8 electrons

The second atom : 8 protons, 10 neutrons and 10 electrons

Required

Comparison

Solution

A. Atom is said to be neutral if the number of protons and electrons is the same

The first atom neutral

The second atom - anion : charge = -2(10 electron-8 proton)

B. isotopes = the same atomic number and different mass number

The first atom : atomic number = 8, mass number = 16

The second atom neutral : atomic number = 8, mass number = 18

Both : isotopes

C. First atom = neutral, second atom anion (charge = -2)

D. Can exist in nature

Answer is : It is a good thermal and electrical conductor. -The main point to be noted is that aluminium is a highly reactive element and still it is used for making cooking utensils. The reason is that aluminium has a very high affinity for oxygen. So, it reacts with oxygen and forms a layer of aluminium oxide on its surface.

Answer:

This is because aluminium reacts with oxygen present in air to form a thin layer of aluminium oxide . This oxide layer is very stable and prevents further reaction of aluminium with oxygen . Also , it is light in weight and a good conductor of heat Hence , it is used to make cooking utensils .

Explanation:

Believe it

Answer:

dry cell

Explanation:

because it stops when salt distribution becomes equal as bridge is not added

Answer:

a

Explanation:

a p e x :)

Answer:

Radio wave

Explanation:

Radio waves are a type of electromagnetic wave radiation with wavelengths in the electromagnetic spectrum longer than infrared light

A seismic wave is an elastic wave generated by an impulse such as an earthquake or an explosion.

Sound and water waves are mechanical waves; meaning, they require a medium to travel through.

Answer:

28 %

Explanation:

Mass mass N2O = 28 + 16 = 44 mass nitrogen = 2 x 14 = 28 % nitrogen Chemistry.

1.999 mol gas

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Atomic Structure

Step 1: Define

1.204 × 10²⁴ atoms gas

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

Step 4: Check

Follow sig fig rules and round. We are given 4 sig figs.

1.99934 mol gas ≈ 1.999 mol gas

Answer:

12

Explanation:

Answer:

If the mass of an object increases, then its kinetic energy will increase proportionally because mass and kinetic energy have a linear relationship when graphed.

Explanation:

is correct answer

Answer:

Sample Response: If the speed of an object increases, then its kinetic energy will increase proportionally because speed and kinetic energy have a linear relationship when graphed.

Explanation:

Answer:

Glucose

Explanation:

Glucose is broken down into water and carbon dioxide.

hope this helps! :)

i tried i hope this helps hun  word “rain forest” implies that these are the some of the world’s wettest ecosystems. Rain forests generally receive very high rainfall each year, although the exact amount varies among different years and different rain forests.  For example, South America’s tropical rain forests receive between 200 and 300 centimetres (80 and 120 inches, or 6.5 to 10 feet!) of rain in a typical year. Despite relatively consistent rain in these ecosystems, there are distinct dry seasons in some rain forests. Wet and dry seasons of tropical rain forests vary in their timing, duration and severity around the globe. Tropical rain forests also have high humidity; about 88% during the wet season and approximately 77% in the dry season.

Answer: a) [tex]78.2m^2[/tex]

b) [tex]1.2\times 10m^2[/tex]

c) [tex]2.5m^2[/tex]

d) [tex]81.1m^2[/tex]

Explanation:

Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.

Rules for significant figures:

1. Digits from 1 to 9 are always significant and have infinite number of significant figures.

2. All non-zero numbers are always significant.  

3. All zero’s between integers are always significant.

4. All zero’s preceding the first integers are never significant.

5. All zero’s after the decimal point are always significant.

The rule apply for the multiplication is :

The least number of significant figures in any number of the problem determines the number of significant figures in the answer.

a) [tex]24m\times 3.26m=78.2m^2[/tex]    

b) [tex]120m\times 0.10m=1.2\times 10m^2[/tex]

c) [tex]1.23m\times 2.0m=2.5m^2[/tex]

d) [tex]53.0m\times 1.53m=81.1m^2[/tex]

Answer:

H₂O₂

Explanation:

Hydrogen peroxide is a typical example of a compound molecule. A compound is made up of one or more atoms that are combined together in a definite grouping.

The properties of a compound is different from those of the elements that combines to from them.

Answer:

B. Geostationary Operational Environmental Satellite

Explanation:

Hope this helps!

Answer:

B

Explanation:

I’m studying it for you!

Answer:

The amount of CaCO₃ Jeeves needs to find is approximately 71.392 grams

Explanation:

The given parameters are;

The mass of the CaO required = 40 g

The chemical reaction for the production of CaO from CaCO₃ is given as follows;

CaCO₃(s) → CaO(s) + CO₂(g)

Therefore, 1 mole of CaCO₃ produces 1 mole of CaO and 1 mole of CO₂,

The molar mass of CaO = 56.0774 g/mol

Number of moles, n = Mass/(Molar mass)

The number of moles of CaO = 40 g/(56.0774 g/mol) ≈ 0.7133 moles of CaO

Therefore, given that 1 mole of CaO is produced from 1 mole of CaCO₃ 0.7133 moles of CaO will be produced from 0.7133 moles of CaCO₃

The molar mass of CaCO₃ = 100.0869 g/mol

Mass = The number of moles × The molar mass

∴ The mass of CaCO₃ Jeeves needs to find = 0.7133 moles × 100.0869 g/mol ≈ 71.392 g

The mass of CaCO₃ Jeeves needs to find ≈ 71.392 grams.

Answer:

b. 0.50 moles

Explanation:

To solve this problem we use Avogadro's number (6.023x10²³ atoms/mol).

By dividing the number of atoms (or molecules) by that number, we can calculate how many moles they represent.

So the answer is option b. 0.50 moles.

Answer:

1 mole of O₂ has more mass compared to 1 mole of Na

Explanation:

1 mole oxygen atom and 1 mole of Na atom has the same number of particles.

A mole of any substance has the Avogadro number of particles which is

6.02 x 10²³

Mass of a substance  = number of moles x molar mass

   Molar mass of O₂  = 2(16)  = 32g/mol

   Molar mass of Na = 23g/mol

Mass of O₂ = 1 x 32  = 32g

Mass of Na = 1 x 23 = 23g

So, 1 mole of O₂ has more mass compared to 1 mole of Na

Answer:

d. Electrons have a negative charge and are lighter than protons

Explanation:

The best statement that describes electrons is that electrons are negatively charged and are lighter than protons.

There are three known subatomic particles which are:

The mass of the protons and neutrons are similar.

Electrons are lighter than both protons and neutrons.

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:

O Chlorine is more reactive than bromine.

Explanation:

From this experiment we can conclude that chlorine is more reactive than bromine and it is the reason why the reaction is able to proceed.

Answer:

There are 1.4754246675000002e+24 atoms of Hydrogen within the measurement of 2.45 moles of hydrogen!

Explanation:

Answer:

50 g

Explanation:

Please brainiest

Answer:

0.967mole

Explanation:

Given parameters:

Volume of NH₄Cl  = 21.67L

Unknown:

Number of moles  = ?

Solution:

We assume that the volume was taken at standard temperature and pressure,

 Then;

  Number of moles  = [tex]\frac{volume }{22.4L}[/tex]  

 Number of moles  = [tex]\frac{21.67}{22.4}[/tex]   = 0.967mole