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zysi [14]
2 years ago
13

8th grade Science Help Please Don't go off what i said

Chemistry
1 answer:
julia-pushkina [17]2 years ago
3 0
Actually your answer is correct. Your answer that you picked is correct because the basic SI unit for mass is a kilograms, so therefore your answer is 13kg which you picked.
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Is Acetaminophen ionic, molecular or organic compound
sergejj [24]

Answer:

Organic compound

Explanation:

Acetominophen's molecular formula is C8H9NO2. Right from the formula you can also see that the compound has C (carbon) in it, therefore making it an organic compound (in which the definition is that the compound contains carbon in it).

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3 years ago
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The general electron configuration for atoms of all elements in group 5a is
stiks02 [169]
Well the elements would be N, P, As, Sb, and Bi. Their electron configuration would be N= [He] 2s2 2p3, P= 1s2 2s2 2p6 3s2 3p3, As= [Ar] 3d10 4s2 4p3, Sb=  Kr 4d10 5s2 5p3, and Bi= Xe 4f14 5d10 6s2 6p3.<span />
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3 years ago
What the difference between a sodium atom (Na) and a sodium ion (Nal+)
vichka [17]

Answer:

So a sodium atom has the electronic configuration 2,8,1 meaning it has 1 electron on its outer shell. It has a neutral charge since the number of electrons is equal to the number of protons.

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7 0
2 years ago
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An unknown compound contains 38.7 % calcium, 19.9 % phosphorus and 41.2 % oxygen. what is the empirical formula of this compound
Softa [21]

Answer: Ca3(PO4)2

Explanation:

  • We assume that the sample is 100.0 g.
  • The sample contains 38.7 g of Ca, 19.9 g of P, and 41.2 g of O as the proportions show.
  • Then we can calculate the number of moles of each component (n = m/atomic mass).
  • The number of moles of Ca = 38.7/40.078 = 0.96 mol.
  • The number of moles of P = 19.9/30.97 = 0.64 mol.
  • The number of moles of O = 41.2/15.99 = 2.75 mol.
  • Now, we can get the molar ratios of different components (Ca, P, and O) in the sample by dividing the number of moles of each component by the lower number of moles, that we should divide the number of moles by (0.64).
  • Ca: P: O = (0.96/0.64) : (0.64/0.64) : (2.75/0.64) = 1.5 : 1 : 4.
  • To avoid the fraction of the ratios, we can multiply all ratios by 2.0.
  • Now, the ratio of Ca : P : O will be 3 : 2 : 8.
  • That main the empirical formula of the compound is Ca3P2O8 which can be expressed as calcium phosphate (Ca3(PO4)2).
8 0
2 years ago
What is the half-life of a compound if 42% of a given sample of the compound decomposes in 60 minutes
Rzqust [24]

The half-life of a compound is 76 years for 42% of a given sample of the compound decomposes in 60 minutes.

<h3>What is the expression for rate law for first order kinetics?</h3>

The rate law for first order kinetics is

k = \frac{2.303}{t}log\frac{a}{a-x}

Where

k - rate constant

t - time passed by the sample

a - initial amount of the reactant

a-x - amount left after the decay process

<h3>What is expression for half-life of the compound?</h3>

The expression for the half-life of the compound is

t_{\frac{1}{2} }=\frac{0.693}{k}

Where k is the rate constant

<h3>Calculation for the given compound:</h3>

It is given that

t = 60 minutes

a = 100 g

a-x = 100 g - 42 g = 58 g

(Since it is given that 42% of the given compound decomposes)

Then,

k = \frac{2.303}{60}log\frac{100}{58}

  = 9.08 × 10^{-3} years^{-1}

Then, the half-life of the compound is

t_{\frac{1}{2} }=\frac{0.693}{k}

    = \frac{0.693}{9.08*10^{-3} }

    = 76.3 years ≅ 76 years

Therefore, the half-life of the given compound is 76 years.

Learn more about rate law for first order kinetics here:

brainly.com/question/24080964

#SPJ4

3 0
1 year ago
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