Select two correct answers.

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[]kingdom

Answer:

Calcium

Explanation:

I just checked the periodic table! This is right checked twice, I hope this helped first time answering a question. Good luck!

Answer:

3 different elements are present in the compound.

Answer:

yes because it is right and because

Answer: The answer is true.

Explanation: You picked 1 5 6 9 which is correct, I think you picked that but I can't see

Answer:

I think the person is not move

Explanation:

b/c the net force is zero............. 100 w + 100 E

............... 100+(-100 = 0

Answer:

I'm pretty sure this doesn't really connect with chemistry much but the answer should be Schedule 1 as stated by the Drug enforcement agency.

Example #1 write the chemical formula for Calcium Oxide

Step 1

-Find the Atomic symbol of the metal and non-metal on the periodic table

CaO

Step 2

Find the charges for Calcium and Oxygen

which are Ca 2+ and O 2-

Step 3

Balance out the charges

They are already balanced out

Here´s the chemical formula for Calcium Oxide

CaO

Example 2 write the chemical formula for Aluminum Oxide

Step 1

-Find the Atomic symbol of the metal and non-metal on the periodic table

A

l

O

Step 2

Find the charges for Aluminum and Oxygen

Which are Al 3+ and O 2-

Step 3

Balance out the charges

You need 2 Aluminum and 3 Oxygen to balance the charges

Al 3+ O 2-

Al 3+ O 2-

= 6 + O 2-

= 6-

Step 4

If you need more then one element to balance out the charges you identify that by using subscripts

Heres your chemical formula for Aluminum Oxide

[tex]Al_{2} O_{3}[/tex]

Answer:

In a pure metal, the force needed to make the layers slide over each other is small. This explains why many pure metals are soft. ... The smaller or bigger atoms distort the layers of atoms in the pure metal. This means that a greater force is required for the layers to slide over each other.

Explanation:

In a pure metal, the force needed to make the layers slide over each other is small. This explains why many pure metals are soft. ... The smaller or bigger atoms distort the layers of atoms in the pure metal.

Explanation:

[tex] \boxed{ \mathsf{F = ma}}[/tex]

The Newton's Second law of motion, also known as The Law of mass and acceleration, derives the given equation in terms of mass, acceleration and force.

It actually states that Force applied on a body is equal to the time rate of change of it's momentum.

Momentum of a body, is the product of it's mass and velocity with which its moving.

This clarifies that objects at rest have zero momentum since they have zero velocity.

If a "source" applies force on an object, it's magnitude would depend on its rate of change of momentum with time.

Since, mass of an object is a fixed entity, so change in momentum would be caused due to change in velocity.

Now, if we happen to have two objects of different mass,

(As, in here, a chair and a large couch) and we have to push them so as to produce the same change in momentum, the force applied on a couch would be more than that applied on the chair.

This is simply because,

Force = mass × acceleration

If acceleration for both the objects is fixed, the force applied differs due to theur difference in mass.

Note here that Force I'd directly proportional to mass.

The greater the mass is, the higher is the force required to produce same acceleration.

Thus, objects with higher mass will require a greater amount of force to have the same acceleration as the object of light weight.

Answer:They can be spread through skin contact, bodily fluids, airborne particles, contact with feces, and touching a surface touched by an infected person.

Immunise against infectious diseases.

Wash and dry your hands regularly and well.

Stay at home if you are sick.

Cover coughs and sneezes.

Clean surfaces regularly.

Ventilate your home.

Prepare food safely.

Practise safe sex.

Explanation:

Answer: photosphere.

Explanation:

The part of the Sun commonly called its surface is the photosphere. The word photosphere means "light sphere" – which is apt because this is the layer that emits the most visible light. It’s what we see from Earth with our eyes.

Answer:  Universe

Mass of ordinary matter

The mass of the observable universe is often quoted as 1050 tonnes or 1053 kg. In this context, mass refers to ordinary matter and includes the interstellar medium (ISM) and the intergalactic medium (IGM). However, it excludes dark matter and dark energy.

Density (of total energy): 9.9×10−27 kg/m3 ...

Mass (ordinary matter): 1.5×1053 kg

Contents: Ordinary (baryonic) matter (4.9%); D...

Volume: 3.566×1080 m3

Explanation:  Galaxy

around 1.5 trillion solar masses

Their answer: The galaxy weighs around 1.5 trillion solar masses. This number helps put in perspective how very small we are. Take, for instance, where stars in the Milky Way fit in.

Ca(OH)2 +2 HBr → CaBr2 + 2 H2O 

Answer:

Only chemical equation uses arrow instead of = sign

Answer:

Only chemical equation uses an arrow instead of a = sign.

A chemical equation depicts a chemical reaction by utilising chemical formulae and symbols to depict the reactants, products, and chemical changes that take place. In a chemical equation, the arrow indicates the direction of the reaction and is commonly depicted as a single arrow pointing from the reactants to the products. In contrast, the equals sign (=) is commonly used in mathematical equations to indicate that two expressions have the same value.

While numbers are used to indicate the relative proportions of reactants and products and minus signs are used to indicate reactants or products in the form of ions, the arrow is the most distinguishing feature that distinguishes chemical equations from mathematical equations.

Answer:

In a chemical reaction, substances (elements and/or compounds) called reactants are changed into other substances (compounds and/or elements) called products. You can't change one element into another in a chemical reaction — that happens in nuclear reactions.

Explanation:

Explanation:

Thus, reactions in which products can be converted to reactant is called Reversible reaction.

Answer:

Physical Change

Explanation:

Answer:

cell

Explanation:

Cells are the most simple, basic units of life

Answer:

the CELL is the basic unit of life.

Explanation:

I had this is my science lesson

have a great day!

hope this helps!

feel free to mark as brainliest! ;)

Answer:

The ground state represents the lowest-energy state of the atom.

Explanation:

sd

Answer:

it would be 53

Explanation:

because 4.00 L at 158kPa and 28c would be 53 grams of oxygine

Answer:

liquid matter

Explanation:

Answer:

The observer effect is the answer.

Answer:

i think this would be an example of a physical change because here the substance is changing directly from a solid to a gas without passing through the liquid state which means that the composition of the substance has not changed and remains the same. This is also called sublimation.

Answer: 153.8865g?

Explanation:

On the periodic table, hydrogen and helium are the only two elements in the first row, or period, which reflects that they only have electrons in their first shell. Hydrogen and helium are the only two elements that have electrons exclusively in the 1 s 1s 1s orbital in their neutral, non-charged, state.

The volume of carbon dioxide produced when 375 mL of a 75.0% ethanol solution by mass with a density of 1.22 g/mL reacts with excess oxygen is  667.52 L.

We are told in the question that the solution contains 75.0% ethanol solution by mass.

Hence;

Density of solution = mass/volume

mass = Density × volume = 1.22 g/mL × 375 mL = 457.5 g

Mass% = mass of solute/ mass of solution × 100

Mass of solute = x

Mass of solution = 457.5 g

Mass percent = 75.0%

Substituting values;

75 = x/457.5 + x × 100

75/100 = x/457.5 + x

0.75(457.5 + x) = x

343.125 + 0.75x = x

343.125  = x -  0.75x

x = 343.125/0.25

x = 1372.5 g

The equation of the reaction is;

C2H6O(l) + 3O2(g) → 2CO2(g) + 3H2O(l)

Number of moles of ethanol =  1372.5 g/46 g/mol = 29.8 moles

From the reaction equation;

2 moles of ethanol produces 2 moles of carbon dioxide

29.8 moles of ethanol also produces 29.8 moles of carbon dioxide

If 1 mole of carbon dioxide occupies 22.4 L

29.8 moles of carbon dioxide occupies 29.8 moles × 22.4 L/ 1 mole

= 667.52 L

Learn more: https://brainly.com/question/17638582

Answer:

Its B all the others arent true and also dont make any sense

Explanation:

Sodium has a lower ionization energy than magnesium describes why sodium reacts vigorously than magnesium chloride.

Therefore, sodium is more reactive than magnesium chloride because of lower ionization energy.

For more details on sodium reactivity, check the link below.

https://brainly.com/question/6837593

In which one element replaces a similar element in a compound?

A single-replacement reaction

A single-replacement reaction is a reaction in which one element of a compound is replaced by another.