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2 years ago

Help! Locks at 12

Chemistry

2 answers:

marta [7]2 years ago

4 0

Answer is #4 (neutrons)

Explanation:

Total mass before the reaction is 236 amu. The total mass of the two elements is 233 amu. This means that there are 3 amus carried by element X. Looking at the total atomic number of the two elements after reaction, it's 92, the same as the one at the beginning. This means that element X has zero atomic number, which could only be a neutron.

In-s [12.5K]2 years ago

3 0

Answer: is 4

Explanation:

I was doing the same one

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Which colligative property is employed when salt is put on an icy sidewalk to melt ice?

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Which statement describes an intensive property of matter? <br>

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Answer:

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Explanation:

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A solution has a [OH-] of 1 × 10-9. What is the pOH of this solution?

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3 years ago

You determine the volume of your plastic bag (simulated human stomach) is 1.08 L. How many grams of NaHCO3 (s) are required to f

dsp73

Answer:

3.636 grams of sodium bicarbonate is required.

Explanation:

Using ideal gas equation:

PV = nRT

where,

P = Pressure of gas = 753.5 mmHg = 0.9914 atm

( $1 atm = 760 mmHg$ )

V = Volume of gas = 1.08 L

n = number of moles of gas = ?

R = Gas constant = 0.0821 L.atm/mol.K

T = Temperature of gas = 24.5 °C= 297.65 K

Putting values in above equation, we get:

$(0.9914 atm)\times 1.08 L=n\times (0.0821L.atm/mol.K)\times 297.65K\\\\n=0.0438 mole$

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Actual moles of carbon dioxide formed: 49.4% of 0.0438 mole

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According to reaction ,1 mol is obtained from 2 moles of sodium bicarbonate.

Then 0.02164 moles f carbon dioxide will be obtained from:

$\frac{2}{1}\times 0.02164 mol=0.04328 mol$

Mass of 0.04328 moles pf sodium bicarbonate:

0.04328 mol × 84 g/mol = 3.636 g

3.636 grams of sodium bicarbonate is required.

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3 years ago

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Answer:

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