A gas occupies a volume of 160 ml at 36° C and 970mm Hg. What is the volume at STP?

Why have we not drilled or mined deeper into earth ??

alexdok [17]

<span>Scientists have determined that the center of the earth is 6371 km below the surface. But how has this been determined? Many people might answer that question by saying scientists can drill into the Earth with machines. However, the drilling rigs that scientists use can only drill about 20 km in the Earth which is not very deep! In other words, we can only drill into upper part of the crust of the earth. Extremely high temperatures and pressures within the Earth make drilling into it very difficult</span>

8 0

2 years ago

A sample of Francium-212 will decay to one sixteenth of its original amount after 80 minutes. What is the half-life of Francium-

lbvjy [14]

20 minutes.

The sample would lose one half the quantity of francium in each half-life.

$1/16 = 1/2^{4} = 1/2 \times1/2 \times1/2 \times1/2$

Thus a mass decrease by a factor of 16 would correspond to a period of four half-lives. It took 80 minutes for the sample to lose all these francium, therefore

$t_{1/2} = 80/4 = 20$ minutes.

6 0

3 years ago

What must be true for a car to move forward at a constant speed? The forward fore of the car is....?

4vir4ik [10]

Constant. you have to continuously apply the same amount of force to achieve constant velocity

4 0

3 years ago

How many grams of Fe will be produced if 705.0g of H20 are produced?

fredd [130]

<h3>Answer:</h3>

2265 g Fe₃O₄

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

<u>Math</u>

<u>Pre-Algebra</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

<u>Stoichiometry</u>

Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

[RxN - Balanced] Fe₃O₄ + 4H₂ → 3Fe + 4H₂O

[Given] 705.0 g H₂O

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

[RxN] 4 mol H₂O → 1 mol Fe₃O₄

Molar Mass of H - 1.01 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of Fe - 55.85 g/mol

Molar Mass of H₂O - 2(1.01) + 16.00 = 18.02 g/mol

Molar Mass of Fe₃O₄ - 3(55.85) + 4(16.00) = 231.55 g/mol

<u>Step 3: Convert</u>

Set up stoich: $\displaystyle 705.0 \ g \ H_2O(\frac{1 \ mol \ H_2O}{18.02 \ g \ H_2O})(\frac{1 \ mol \ Fe_3O_4}{4 \ mol \ H_2O})(\frac{231.55 \ g \ Fe_3O_4}{1 \ mol \ Fe_3O_4})$
Multiply/Divide/Cancel units: $\displaystyle 2264.74 \ g \ Fe_3O_4$

<u>Step 4: Check</u>

<em>Follow sig fig rules and round. We are given 4 sig figs.</em>

2264.74 g Fe₃O₄ ≈ 2265 g Fe₃O₄

5 0

2 years ago

Which metal is the best choice for recovering copper (reacting with copper) from the solution? Fe, Ag, Zn, or Al

Gnoma [55]

Answer: The correct option is Aluminium.

Explanation: To recover copper from the solution, we require a metal which can easily displace copper from the solution.

The reactions in which metal displaces another metal in a chemical reaction are known as single displacement reactions. These reactions are studied using reactivity series.

$A+BC\rightarrow AC+B$

A is more reactive than B.

The metal which lie above in the reactivity series will easily displace the metal which lies below in the reactivity series.

From the given options, Aluminium is the most reactive of all the metals and hence, it is the best choice for recovering copper from its solution.

3 0

3 years ago