What are the correct coefficients when this equation is balanced? K + Br2 KBr

B. What useful functions do oxidation numbers

disa [49]

Explanation:

b. What useful functions do oxidation numbers serve?

It is used to show oxidation and reduction (loss and gain of electrons)

b. How many molecules are in 1 mole of molecules?

1 mole = 6.022 * 10^23 molecules

c. What is the name given to the number of molecules in 1 mole?

Avogadro's Number of molecules

21. a. What is the molar mass of an element?

This is the mass of an element divided by the number of moles.

Molar mass = Mass / Number of moles

b. Write the molar mass rounded to two decimal places of carbon, neon, iron and uranium.

amu = Atomic Mass Unit

Carbon = 12.01 amu

Neon = 20.18 amu

Iron = 55.85 amu

Uranium = 238.03 amu

7 0

3 years ago

Carbon dioxide (CO2) is a gas at room temperature and pressure. However, carbon dioxide can be put under pressure to become a "s

Lunna [17]

Answer:

The mass of this 25 mL supercritical CO2 sample has a mass of 11.7g

Explanation:

Step 1: Given data

The supercritical CO2 has a density of 0.469 g/cm³ (or 0.469 g/mL)

The sample hasa volume of 25.0 mL

Step 2: Calculating mass of the sample

The density is the mass per amount of volume

0.469g/cm³ = 0.469g/ml

The mass for a sample of 25.0 mL = 0.469g/mL * 25.0 mL = 11.725g ≈ 11.7g

The mass of this 25 mL supercritical CO2 sample has a mass of 11.7g

5 0

4 years ago

A substance made of metal atoms only?

SVEN [57.7K]

It has to be a metal, it can't be anything else.

5 0

3 years ago

what is the molecular formula of a compound that contains 38% c, 45% n and 16% h if 0.157 g of the compound occupies 125 ml with

EastWind [94]

The molecular formula of the given compound is CH₅N.

<h3>What is the ideal gas equation?</h3>

The ideal gas law has defined the product of the volume and pressure as equal to the product of the gas constant (R) and absolute temperature of the gas.

The mathematical equation of the ideal gas law is as follows:

PV = nRT

The temperature of the compound, T = 22° C = 295 K

The pressure of the compound, P = 99.5 KPa = 0.982 atm

The volume of the compound, V = 125 ml = 0.125 L

0.125 × 0.982 = (0.157 g/M) × 0.082 ×295

M = 31 g/mol

A number of moles of C = 0.157 ×0.37/12 = 0.00484

A number of moles of N = 0.157 ×0.45/14 = 0.00504

A number of moles of H = 0.157 ×0.16/1 = 0.0251

The simplest ratio of C: N: H is 1 : 1 : 5

The empirical formula of the given compound is CH₅N.

The molecular formula of the compound is CH₅N as the molecular mass is equal to 31 g/mol.

Learn more about ideal gas equation, here:

brainly.com/question/3637553

#SPJ1

4 0

1 year ago

Given the following list of densities, which materials would float in a molten vat of lead provided that they do not themselves

vampirchik [111]

Answer:

b. glass and charcoal

Explanation:

Step 1: Given data

Density of Pb: 11.4 g/mL

Density of Glass: 2.6 g/mL

Density of Au: 19.3 g/mL

Density of charcoal: 0.57 g/mL

Density of platinum: 21.4 g/mL

Step 2: Determine which material will float in molten lead

Density is an intrinsic property of matter. Less dense materials float in more dense materials. The materials whose density is lower than that of lead and will therefore float on it are glass and charcoal.

8 0

3 years ago