Calculate the number of kilojoules to warm 125 g of iron from 23.5 °C to 78.0 °C.

Suggest a method for measuring the size of the colony.

Evgen [1.6K]

Answer:

Counting the number of colonies that arise on a pour plate can calculate the concentration by multiplying the count by the volume spread on the pour plate. Direct counting methods are easy to perform and do not require highly specialized equipment, but are often slower than other methods

Explanation:

I hope it will help you

7 0

3 years ago

What kind of elements are on the left side of the zig-zag line on the periodic table?

Ber [7]

Metals are to the left of the zig-zag, nonmetals are to the right, and metalloids lie on/beside the line.

3 0

3 years ago

Which mixture can be classified as a homogeneous mixture?

Reika [66]

Anything can be homogenous as long as you can only see the same type of liquid
think about it like this
orange juice with pulp is Hetero
orange juice with no pulp is homo

3 0

3 years ago

Read 2 more answers

If 56.8 ml of bacl2 solution is needed to precipitate all the sulfate ion in a 554 mg sample of na2so4 (forming baso4), what is

IrinaVladis [17]

<span>0.0687 m The balanced equation is BaCl2 + Na2SO4 ==> BaSO4 + 2 NaCl Looking at the equation, it indicates that there's a 1 to 1 ratio of BaCl2 and Na2SO4 in the reaction. So the number of moles of each will be equal. Now calculate the number of moles of Na2SO4 we had. Start by looking up atomic weights. Atomic weight sodium = 22.989769 Atomic weight sulfur = 32.065 Atomic weight oxygen = 15.999 Molar mass Na2SO4 = 2 * 22.989769 + 32.065 + 4 * 15.999 = 142.040538 g/mol Moles Na2SO4 = 0.554 g / 142.040538 g/mol = 0.003900295 mol Molarity is defined as moles per liter, so let's do the division. 0.003900295 mol / 0.0568 l = 0.068667165 mol/l = 0.068667165 m Rounding to 3 significant figures gives 0.0687 m</span>

3 0

4 years ago

When fluorine gas combines with water vapor, the following reactions occurs.

jonny [76]

Hello!

The Chemical reaction is the following:

2F₂(g) + 2 H₂O(g) → O₂(g) + 4HF(g)

If we assume that all the gases are ideal gases, we can describe the coefficients of this reaction as Volume rather than moles, so we can apply the following equations:

$2 L F_2* \frac{2 L H_2O}{2 L F_2}=2 L H_2O \\ \\ 2 L F_2* \frac{1 mol O_2}{2 L F_2}=1 mol O_2 \\ \\ 2 L F_2* \frac{4 mol HF}{2 mol F_2}= 4 mol HF$

So, 2 L of Water Vapor reacts with the fluorine; and 1 L of Oxygen and 4 L of Hydrogen Fluoride are produced.

Have a nice day!

6 0

3 years ago