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3 years ago

An (blank) determines what will be tested in a scientific experiment

1 answer:

6 0

The answer would be hypotheis since its an theory that isnt proven yet which would involve a scientist to expertiment to make the hypothesis true or valid

You might be interested in

How many atoms are in 58.93 grams of cobalt (Co)?

Vadim26 [7]

If you have 58.93g of Co it means that you only have 1 mol (use a periodic table to find the answer, if you had more find it by proportion, it's easier).
There's 6.022 x 10^23 atoms per mol so you have 6.022 x 10^23 atoms of Co.
(once again if you had more mol, you could find the answer by proportions).

7 0

3 years ago

A gas occupies a volume of 4.50 L at 44 kPa. What would be the new volume at 50 kPa?

oksano4ka [1.4K]

Explanation:

P1= 44 kpa

P2= 50 kpa

V1= 4.50 L

V2= ?

P1 V1= P2 V2

44 × 4.50 = 50 × V2

198= 50 × V2

V2 = 198/ 50

V2= 3.96 L "the new volume"

5 0

3 years ago

A compound has the empirical formula CH2O. If the compound’s molecular mass is 180 g/mol, determine the molecular formula of the

Umnica [9.8K]

The molecular formula will be a multiple of the empirical CH2O. One unit of CH2O has a mass of 12+2*1+16 = 30 g. This means that if our compound has a molecular mass of 180 g/mol, we can divide 180 / 30 = 6 units, and our compound has 6 units of CH2O. This means that its molecular formula is C6H12O6.

3 0

2 years ago

formic acid buffer containing 0.50 M HCOOH and 0.50 M HCOONa has a pH of 3.77. What will the pH be after 0.010 mol of NaOH has b

HACTEHA [7]

Answer:

pH = 3.95

Explanation:

It is possible to calculate the pH of a buffer using H-H equation.

pH = pka + log₁₀ [HCOONa] / [HCOOH]

If concentration of [HCOONa] = [HCOOH] = 0.50M and pH = 3.77:

3.77 = pka + log₁₀ [0.50] / [0.50]

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Knowing pKa, the NaOH reacts with HCOOH, thus:

HCOOH + NaOH → HCOONa + H₂O

That means the NaOH you add reacts with HCOOH producing more HCOONa.

Initial moles of 100.0mL = 0.1000L:

[HCOOH] = (0.50mol / L) ₓ 0.1000L = 0.0500moles HCOOH

[HCOONa] = (0.50mol / L) ₓ 0.1000L = 0.0500moles HCOONa

After the reaction, moles of each species is:

0.0500moles HCOOH - 0.010 moles NaOH (Moles added of NaOH) = 0.0400 moles HCOOH

0.0500moles HCOONa + 0.010 moles NaOH (Moles added of NaOH) = 0.0600 moles HCOONa

With these moles of the buffer, you can calculate pH:

pH = 3.77 + log₁₀ [0.0600] / [0.0400]

3 0

3 years ago

Using the following equation, 2C2H6 +7O2 -->4CO2 +6H2O, if 2.5g C2H6 react with 170g of O2, how many grams of water will be p

kirill [66]

The mass of water (H₂O) that would be produced is 4.5 g

<h3>Stoichiometry </h3>

From the question, we are to determine the mass of water that would be produced.

From the given balanced chemical equation

2C₂H₆ +7O₂ → 4CO₂ +6H₂O

This means

2 moles of C₂H₆ reacts with 7 moles of O₂ to produce 4 moles of CO₂ and 6 moles of H₂O

Now, we will determine the number of moles of each reactant present

For Ethane (C₂H₆)

Mass = 2.5 g

Molar mass = 30.07 g

Using the formula,

$Number\ of\ moles = \frac{Mass}{Molar\ mass}$

Number of moles of C₂H₆ present = $\frac{2.5}{30.07}$

Number of moles of C₂H₆ present = 0.08314 mole

For Oxygen (O₂)

Mass = 170g

Molar mass = 31.999 g/mol

Number of moles of O₂ present = $\frac{170}{31.999}$

Number of moles of O₂ present = 5.3127 moles

Since

2 moles of C₂H₆ reacts with 7 moles of O₂

Then,

0.08314 mole of C₂H₆ will react with $\frac{7 \times 0.08314 }{2}$

$\frac{7 \times 0.08314 }{2}$ = 0.58198 mole

Therefore,

0.08314 mole of C₂H₆ reacts with 0.58198 mole of O₂ to produce 3 × 0.08314 moles of H₂O

3 × 0.08314 = 0.24942 mole

Thus, the number of moles of water (H₂O) produced is 0.24942 mole

Now, for the mass of water that would be produced,

Using the formula,

Mass = Number of moles × Molar mass

Molar mass of water = 18.015 g/mol

Then,

Mass of water that would be produced = 0.24942 × 18.015

Mass of water that would be produced = 4.4933 g

Mass of water that would be produced ≅ 4.5 g

Hence, the mass of water (H₂O) that would be produced is 4.5 g

Learn more on Stoichiometry here: brainly.com/question/14271082

3 0

2 years ago