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3 years ago

An atom of phosphorus has an atomic number of 15 and a mass number of 31. how many protons and neutrons does it contain?

Chemistry

1 answer:

vazorg [7]3 years ago

7 0

Phosphorus has 15 protons and 16 electrons.

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Whas the difference between an element, molecule and compound

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Answer: element is a sotce

Explanation:

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3 years ago

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You want to experiment to see how long it takes for water, hydrogen peroxide, and vinegar to boil. You decide heat up 10 mL of w

aleksley [76]

Answer:

Explanation:

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3 years ago

The vapor pressure of substance X is 100. mm Hg at 1080.°C. The vapor pressure of substance X increases to 600. mm Hg at 1220.°C

artcher [175]

Explanation:

The given data is as follows.

$P_{1}$ = 100 mm Hg or $\frac{100}{760}atm$ = 0.13157 atm

$T_{1}$ = $1080 ^{o}C$ = (1080 + 273) K = 1357 K

$T_{2}$ = $1220 ^{o}C$ = (1220 + 273) K = 1493 K

$P_{2}$ = 600 mm Hg or $\frac{600}{760}atm$ = 0.7895 atm

R = 8.314 J/K mol

According to Clasius-Clapeyron equation,

$log(\frac{P_{2}}{P_{1}}) = \frac{\Delta H_{vap}}{2.303R}[\frac{1}{T_{1}} - \frac{1}{T_{2}}$

$log(\frac{0.7895}{0.13157}) = \frac{\Delta H_{vap}}{2.303 \times 8.314 J/mol K}[\frac{1}{1357 K} - \frac{1}{1493 K}]$

$log (6) = \frac{\Delta H_{vap}}{19.147}[\frac{(1493 - 1357) K}{1493 K \times 1357 K}]$

0.77815 = $\frac{\Delta H_{vap}}{19.147J/K mol} \times 6.713 \times 10^{-5} K$

$\Delta H_{vap}$ = $2.219 \times 10^{5}$ J/mol

= $2.219 \times 10^{5}J/mol \times 10^{-3}\frac{kJ}{1 J}$

= 221.9 kJ/mol

Thus, we can conclude that molar heat of vaporization of substance X is 221.9 kJ/mol.

4 0

3 years ago

TELLURIUM ELECTRONS GAINED OR LOST?

fenix001 [56]

Answer:

Gains

Explanation:

An atom of Tellurium gives off energy when it gains an electron to form an ion of Tellurium.

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3 years ago

An aqueous solution of potassium hydroxide is standardized by titration with a 0.122 M solution of hydrobromic acid. If 22.1 mL

Gemiola [76]

Answer:

The molarity of the potassium hydroxide solution is 0.104 M

Explanation:

Step 1: Data given

Molarity of hydrobromic acid (HBr) = 0.122 M

Volume of potassium hydroxide (KOH) = 22.1 mL = 0.0221 L

Volume of hydrobromic acid = 18.8 mL = 0.0188 L

Step 2: The balanced equation

HBr(aq) + KOH(aq) → KBr(aq) + H2O(l)

Step 3: Calculate moles of HBr

Moles HBr = molarity HBr * volume HBr

Moles HBr = 0.122 M * 0.0188 L

Moles HBr = 0.0022936 moles

Step 4: Calculate molarity of KOH

We need 0.0022936 moles of KOH to neutralize the HBr

Molarity = moles / volume

Molarity KOH = 0.0022936 moles /0.0221 L

Molarity KOH = 0.104 M

The molarity of the potassium hydroxide solution is 0.104 M

4 0

3 years ago