Does iron melt at 1728 degrees Celsius

Hannah does an experiment. She has two colorless chemicals that she mixes together in a beaker. Which of the following indicates

uranmaximum [27]

I am not to sure but is it all 4 of them?

8 0

3 years ago

Read 2 more answers

4. How many moles of gold (Au) are in a pure gold nugget having a mass of 25.0 grams.

ikadub [295]

<h3>Answer:</h3>

0.127 mol Au

<h3>General Formulas and Concepts:</h3>

<u>Math</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

<u>Chemistry</u>

<u>Atomic Structure</u>

Reading a Periodic Table
Moles

<u>Stoichiometry</u>

Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

[Given] 25.0 g Au

[Solve] moles Au

<u>Step 2: Identify Conversions</u>

[PT] Molar Mass of Au - 196.97 g/mol

<u>Step 3: Convert</u>

[DA] Set up: $\displaystyle 25.0 \ g \ Au(\frac{1 \ mol \ Au}{196.97 \ g \ Au})$
[DA] Multiply/Divide [Cancel out units: $\displaystyle 0.126923 \ mol \ Au$

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 3 sig figs.</em>

0.126923 mol Au ≈ 0.127 mol Au

3 0

2 years ago

Read 2 more answers

What do Potassium and Krypton have in common and what are their differences based on their location on the periodic table?

Kamila [148]

Potassium (K) and Krypton (Kr) are in the same period, so they have the same number of electron shells. Potassium is more reactive than Krypton because it only has one valence electron.

K and Kr are both in Period 4, so they each have the n = 1, 2, 3, and 4 shells. Kr is less reactive than K because it already has a complete octet.

“Potassium (K) and Krypton (Kr) are in the same period, so they have the same number of electron shells. Krypton is more reactive than Potassium because it has a full outer shell” is <em>incorrect </em>because having a full outer shell means that the element is unreactive.

“Potassium (K) and Krypton (Kr) are in the same group, so they have the same number of valence electrons. They have different numbers of electron shells” is <em>incorrect </em>for three reasons:

1. K is in Group 1 and Kr is in Group 18.

2. K has one valence electron, and Kr has eight valence electrons.

3. They have the same number of electron shells.

“Potassium (K) and Krypton (Kr) are in the same group, so they have the same number of valence electrons. They have different numbers of electron shells” is <em>incorrect</em> for two reasons:

1. K and Kr have different numbers of valence electrons.

2. They have the same number of electron shells.

8 0

3 years ago

Which two notations represent isotopes of the same element

Mumz [18]

The two notations that represent isotopes of the same element is the one that represented in option 1
The lower number is the number of protons while the upper number is the atomic weight

hope this helps

6 0

3 years ago

Read 2 more answers

Identify the main purpose of the Periodic Table. *

saw5 [17]

The periodic table is one of the most important tools in the history of chemistry. It describes the atomic properties of every known chemical element in a concise format, including the atomic number, atomic mass and relationships between the elements. Elements with similar chemical properties are arranged in columns in the periodic table.

The table thus is a quick reference as to what elements may behave the same chemically or which may have similar weights or atomic structures.

Hope this answer helps you

4 0

3 years ago