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2 years ago

How do you know when writing out equations the state of the element or compound

Chemistry

1 answer:

erica [24]2 years ago

7 0

Answer:

The state of matter is usually written in parentheses as a subscript directly after the element or compound.

You might be interested in

What is the most common isotope of lithium?

Advocard [28]

Lithium-7 is the most common isotope of lithium.

7 0

2 years ago

The amount of fat recommended for somone with a daily diet of 2000 Calories is 65 g. What percent of the calories in this diet w

Doss [256]

Answer:

29.575%

Explanation:

Data provided:

Calories taken in daily diet = 2000

Recommended amount of fat = 65 grams

Average number of calories for fat = 9.1 calories / g

Thus,

Number of calories in the diet with average number of calories for fat

= Recommended amount of fat × Average number of calories for fat

= 65 × 9.1

= 591.5 calories

Therefore,

the percentage of calories in his diet supplied = ( 591.5 / 2000 ) × 100

= 29.575%

6 0

2 years ago

When a 235 92U nucleus is bombarded by neutrons (10n) it undergoes a fission reaction, resulting in the formation of two new nuc

user100 [1]

Answer:

$^{139}_{56}Ba$

Explanation:

The fission reaction taking place given in the question is:

$^{235}_{92}U+^{1}_{0}n\rightarrow ^{A}_{Z}Ba+^{94}_{36}Kr+3^{1}_{0}n$

The mass is conserved in the reaction.

So,

235 + 1 = A + 94 + 3×1

A = 139 g/mol

Also, number o protons remain same. So,

92 = Z + 36

Z = 56

The isotopic symbol is $^{139}_{56}Ba$

5 0

2 years ago

Is. Mg(s) --------------> Mg2+(aq) + 2e−<br><br><br><br>oxidation or reduction?

Kruka [31]

Answer:

Oxidation

Explanation:

Mg loses 2e- for it to gain it's stability hence the reaction above is oxidation

note: Oxidation is the loss of electrons while reduction is the gain of electrons

5 0

2 years ago

A common laboratory reaction is the neutralization of an acid with a base. When 31.8 mL of 0.500 M HCl at 25.0°C is added to 68.

lord [1]

Answer:

The correct answer to the following question will be "90.6 kJ/mol".

Explanation:

The total reactant solution will be:

$(31.8 \ mL+68.9 \ mL)\times 1.07\ g/mL = 107.74 \ g$

The produced energy will be:

$=4.18 \ J/(gK)\times 107.74 \ g\times (28.2-25.0)K$

$=450.35\times 3.2$

$=1441.12 \ J$

The reaction will be:

⇒ $HCl+NaOH \rightarrow NaCl+H_{2}O$

Going to look at just the amounts of reactions with the same concentrations, we notice that they're really comparable.

Therefore, the moles generated by NaCl will indeed be:

= $(\frac{31.8}{1000} \ L)\times (0.500 \ M \ HCl/L)\times \frac{1 \ mol \ NaCl}{1 \ mol \ HCl}$

= $0.0318\times 0.500$

= $0.0159 \ mole \ of \ NaCl$

Now,

= $\frac{1441.12 \ J}{0.0159 \ moles \ NaCl}$

= $906364.7$

= $90.6 \ KJ/mol \ NaCl$

7 0

2 years ago