Who was the first governor of the Massachusetts Bay Colony?

Identify the independent variable and the dependent variable in each of the following hypothesis

Olin [163]

Answer:

Independent variable: different alcohols

Dependent variable: red dye

3 0

3 years ago

Read 2 more answers

What makes a question testable? Can someone help me on this pls it has to be either a 4-5 sentence! this is a science question.

Alexxandr [17]

Answer:

testable questions are answer through observation or an experiment that provides evidence that the questions connects to the scientific concepts rather the opinion feelings

therefore the question can be tested through observation or experiment

7 0

3 years ago

You find a compound composed only of element X and chlorine and you know that the compound is 13.10% X by mass. Each molecule of

8_murik_8 [283]

Answer:

Explanation:

So, the formula for the compound should be:

$XCl_{6}$

Now we assume that we have 1 mol of substance, so we can make calculations to know the molar mass of element X, as follows:

$M_{Cl}=35.45g/mol\\$

So we have that 6 moles weight 212.7g, and we can make a rule of three to know the weight of compound X:

$212.7g\rightarrow 86.9\%\\x\rightarrow 13.1\%\\\\x=\frac{212.7g*13.1}{86.9} =32.06g$

As we used 1 mol, we know that the molar mass is 32.06g/mol

So the element has a molar mass of 32.06 g/mol and an oxidation state of +6, with this information, we can assure that the element X is sulfur, so the compound is $SCl_{6}$

8 0

3 years ago

How many particles are in 2.0 moles of CH4

Whitepunk [10]

Answer: There are 4.8 x 1024 hydrogen atoms in 2.0 moles of CH4

6 0

2 years ago

Read 2 more answers

EXTRA POINTSSS 1. A solution at 25 degrees Celsius is 1.0 × 10–5 M H3O+. What is the concentration of OH– in this solution?

AlekseyPX

Answer:

Concentration of OH⁻:

1.0 × 10⁻⁹ M.

Explanation:

The following equilibrium goes on in aqueous solutions:

$\text{H}_2\text{O}\;(l)\rightleftharpoons \text{H}^{+}\;(aq) + \text{OH}^{-}\;(aq)$ .

The equilibrium constant for this reaction is called the self-ionization constant of water:

$K_w = [\text{H}^{+}]\cdot[\text{OH}^{-}]$ .

Note that water isn't part of this constant.

The value of $K_w$ at 25 °C is $10^{-14}$ . How to memorize this value?

The pH of pure water at 25 °C is 7.
$[\text{H}^{+}] = 10^{-\text{pH}} = 10^{-7}\;\text{mol}\cdot\text{dm}^{-3}$
However, $[\text{OH}^{-}] = [\text{H}^{+}]=10^{-7}\;\text{mol}\cdot\text{dm}^{-3}$ for pure water.
As a result, $K_w = [\text{H}^{+}] \cdot[\text{OH}^{-}] = (10^{-7})^{2} = 10^{-14}$ at 25 °C.

Back to this question. $[\text{H}^{+}]$ is given. 25 °C implies that $K_w = 10^{-14}$ . As a result,

$\displaystyle [\text{OH}^{-}] = \frac{K_w}{[\text{H}^{+}]} = \frac{10^{-14}}{1.0\times 10^{-5}} = 10^{-9} \;\text{mol}\cdot\text{dm}^{-3}$ .

8 0

3 years ago