Someone please help i don’t have much time left

Answer:

Subtracting the number of protons from the atomic mass.

Answer:

Subtract Protons

Explanation:

Since the vast majority of atom's mass is found it's protons and neutrons, Subtracting the Number of Protons ( i.e. the atomic number ) from the atomic mass will give you the calculated number of neutrons in a atom,

Answer:

D. In the atmosphere

Explanation:

convection currents forms in the atmosphere

Answer:

Mass =  142.25 g

Explanation:

Given data:

Mass of Ca(OH)₂ = ?

Number of moles of Ca(OH)₂ = 1.92 mol

Solution:

Formula:

Mass = number of moles × molar mass

Molar mass of Ca(OH)₂ = 74.09 g/mol

by putting values,

Mass = 1.92 mol × 74.09 g/mol

Mass =  142.25 g

Answer:

The soil has a percentage of water by mass of 27.8 %.

Explanation:

Keeping in mind that

we can calculate the mass of water:

We can then calculate the mass percentage of water in the soil:

Answer: B

Explanation:

Answer: product

Explanation:

Each substance written to the right of the arrow in a chemical equation is referred to as a product.

When writing a chemical equation, the substance that's written to the left of arrow in the equation is the reactants.

On the other hand which is the right side is the product.

Answer:

construct using only recycled materials ^^

Explanation:

Answer:

0.52 g of KNO₃ are contained in 19.7 mL of diluted solution.

Explanation:

We can work on this problem in Molarity cause it is more easy.

Molarity (mol/L) → moles of solute in 1L of solution.

100 mL of solution = 0.1 L

We determine moles of solute: 44.7 g . 1mol /101.1 g = 0.442 mol of KNO₃

Our main solution is 0.442 mol /0.1L = 4.42 M

We dilute: 4.42 M . (11.9mL / 200mL) = 0.263 M

That's concentration for the diluted solution.

M can be also read as mmol/mmL, so let's find out the mmoles

0.263 M . 19.7mL = 5.18 mmol

We convert the mmol to mg → 5.18 mmol . 101.1 mg / mmol = 523.7 mg

Let's convert mg to g → 523.7 mg . 1 g / 1000 mg = 0.52 g

How many grams of zinc (Zn) are in 32.7 g of Zn?

Answer:

32.7g

Explanation:

The mass of Zinc in the given substance is 32.7g.

Mass is the quantity of matter contained in a substance. The sum total of the amount of matter is the mass.

Since this problem gives us 32.7g of Zn then the substance will also contain 32.7g of Zinc.

Even when the Zinc is used in chemical reactions, we are expected to produce an equal amount of zinc as the product.

This way, mass is always conserved.

Answer:

All employees should know how to work the system

Answer:

D. spectator ions.

Explanation:

Hello!

In this case, when going over net ionic equations by which precipitation reactions are analyzed, we can consider the example of lead (II) nitrate with potassium iodide to yield insoluble lead (II) iodide and soluble potassium nitrate according to:

[tex]2KI(aq)+Pb(NO_3)_2(aq)\rightarrow PbI_2(s)+2KNO_3(aq)[/tex]

Whereas aqueous species remain in solution:

[tex]2K^+(aq)+2I^-(aq)+Pb^{2+}(aq)+2(NO_3)^-(aq)\rightarrow PbI_2(s)+2K^+(aq)+2(NO_3)^-(aq)[/tex]

It means that potassium and nitrate ions are spectator ions because they are not involved in the precipitation reaction, which is represented by the net ionic one:

[tex]2I^-(aq)+Pb^{2+}(aq)\rightarrow PbI_2(s)[/tex]

Thus, the answer to this question is D. spectator ions.

Best regards!

Answer:

color

Explanation:

Answer:

D

Explanation:

The five conditions of chemical change: color chage, formation of a precipitate, formation of a gas, odor change, temperature change and the others are just physical changes that would happen if you change containers, or let it evaporate.

The theoretical yield : = 10.251 g

Given

Reaction

3H₂(g)+N₂(g)→2NH₃(g)

1.81 g H₂

10.2 g N₂

2.19 g NH₃

Required

The theoretical yield

Solution

Find limiting reactant :

H₂ : 1.81 g : 2 g/mol = 0.905 mol

N₂ : 10.2 g : 28 g/mol = 0.364 mol

mol : coefficient

H₂ = 0.905 : 3 = 0.302

N₂ = 0.364 : 1 = 0.364

H₂ as a limiting reactant(smaller ratio)

Moles NH₃ based on H₂, so mol NH₃ :

= 2/3 x mol H₂

= 2/3 x 0.905

=0.603

Mass NH₃ :

= mol x MW

=0.603 x 17 g/mol

= 10.251 g

Answer: 1.67

D=M/V

(D=57.4/34.3)= 1.67

Answer:

well heat travels by conduction, convection, and radiation but I think it's 2.

Explanation:

heat travels to colder things trying to make a balanced temperature for both of the objects.

Answer:

its burning

Explanation:

can you please try to answer my latest question i need it badly please and thank you

Answer:

Burning.

Explanation:

Example:

Wood burns and produces smoke and ash.

The lethal dose and how ounces of soda in a can of soda is not given, however, the standard lethal dose and volume of soda are given as below:

Lethal dose: 10 gm of caffeine

The volume of soda per can =  12oz/can

Answer:

The correct answer is - 324.254 cans or round up to 325 cans. Ans.

Explanation:

Given:

2.57 mg caffeine / 1oz

12oz / 1can

Lethal dose: 10.0g or 10,000mg of caffeine

Solution:

Caffeine per soda can = (2.57 mg caffeine / 1oz) * (12oz / 1can) = 30.84 mg caffeine / 1can.

lethal dose would be in =

(10,000mg caffeine) * (1can / 30.84 mg caffeine) = 324.254 cans or round up to 325 cans. Ans.

Answer:

The sun will appear to rise and set more slowly

have a nice day! (^o^)

Answer:

M =  0.125 M

Explanation:

Given data:

Molarity = ?

Volume of solution = 2 L

Mass of K₂SO₄ = 43.55 g

Solution;

Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.

Formula:

Molarity = number of moles of solute / L of solution

Number of moles of solute:

Number of moles = mass/molar mass

Number of moles = 43.55 g / 174.26 g/mol

Number of moles = 0.25 mol

Molarity:

M =  0.25 mol / 2 L

M =  0.125 M

Answer:

Explanation:

The average kinetic energy for an ideal gas is directly proportional to the temperature. The average kinetic energy of the gas is a measure of the temperature of the gas molecule

Also, the average speed is usually proportional to the square root of temperature.

Similarly, there is a noticeable increase in K.E and speed in regard to temperature but sometimes it is not usually proportional.

However, provided that there is more temperature in Xe as compared to He, then after the mixture of both takes place at equilibrium; the temperature tends to fluctuate between (25 - 50)°C

Thus, since there is a decrease in temperature in Xe, both the average kinetic energy as well as the speed too will also decrease.

Answer:

The sun will appear to rise and set more slowly

have a nice day! (^o^)

Answer:

The ring is probably not geniune.

Explanation:

To solve this problem we first need to calculate the density of the ring:

The mass is given by the problem, and we're able to assess the volume by keeping in mind Archimede's principle (the volume of water displaced by an object is equal to the object's volume).

Given that the ring density is significantly lower than the density of pure platinum, the ring is probably not geniune.

Answer:

292 g

Explanation:

Step 1: Given data

Step 2: Calculate the mass corresponding to 2.17 moles of copper (II) chloride

We will use the following expression.

m = n × M

m = 2.17 mol × 134.452 g/mol = 292 g

2.17 moles of copper (II) chloride weigh 292 g.

Answer:

Hydrosphere

Explanation:

The biosphere simply refers to the zone of life found on earth. It refers to the portion of the earth inhabited by living things.

The biosphere is divided into three, namely; hydrosphere, atmosphere and lithosphere.

The atmosphere is simply the layer composed of air, the lithosphere is the solid part of the earth while the hydrosphere is the part composed of water.

Since jelly fish is an aquatic animal, it will certainly inhabit the hydrosphere. Hence the answer above.

Answer:

7.90

Explanation:

Gay-Lussacs law states that P1/T1 = P2/T2

if:

P1 = 6.32

T1 (in Kelvins) = 25.1 + 273.1 =298.2

P2= ?

T2 = 100 + 273.1 = 373.1

so

6.32/298.2 = P2/373.1

P2 = 7.90

Answer:

1 mole of platinum

Explanation:

To obtain the number of mole(s) of platinum present, we need to determine the empirical formula for the compound.

The empirical formula for the compound can be obtained as follow:

Platinum (Pt) = 117.4 g

Carbon (C) = 28.91 g

Nitrogen (N) = 33.71 g

Divide by their molar mass

Pt = 117.4 / 195 = 0.602

C = 28.91 / 12 = 2.409

N = 33.71 / 14 = 2.408

Divide by the smallest

Pt = 0.602 / 0.602 = 1

C = 2.409 / 0.602 = 4

N = 2.408 / 0.602 = 4

The empirical formula for the compound is PtC₄N₄ => Pt(CN)₄

From the formula of the compound (i.e Pt(CN)₄), we can see clearly that the compound contains 1 mole of platinum.