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Allushta [10]
3 years ago
12

Which of the following are examples of sampling bias

Chemistry
1 answer:
levacccp [35]3 years ago
4 0

Answer:

the first and the third one.

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A piece of iron is heated to 120'C then placed in a calorimeter containing 50g of water. The water temperature is raised from 30
Lana71 [14]

Answer:

Mass of iron = 59.375 gm

Explanation:

Calories ( or joules) are added to the water by the hot steel so at the endpoint they are BOTH at 40 C

 The water gains:

     4.18  j/g-C  * 50 * (40-30 C) = 2090 j

The steel gave up 2090 j going from 120 to 40 C

2090 = .44 j/g-C  * m * (120-40)    solve fro m = 59.375 gm

3 0
2 years ago
Please help me people it’s due today at 6:00pm please help me please please
vovangra [49]

Explanation:

gravity if it's incorrect sorry

7 0
2 years ago
Read 2 more answers
Show dipole dipole force of water and ethyll alcohol.​
Alexeev081 [22]

Answer:

Water: H2O --> [H+] + [OH-]

Ethyl alcohol: C2H5OH --> [C2H5O-] + [H+]

Explanation:

Dipole-dipole force is observed when an ionic compound ionizes (forms ions), revealing its slightly positive ion and slightly negatively ion.

The chemical formula of Water is H2O.

H2O --> [H+] + [OH-]

The chemical formula of ethyl alcohol is C2H5OH.

C2H5OH --> [C2H5O-] + [H+]

Note the positive and negative parts of both water and ethyl alcohol as expressed in the equations above.

6 0
3 years ago
For the reaction N2O4(g) ⇋ 2NO2(g), Kc = 0.25 at 98°C. At a point during the reaction, the concentration of N2O4 = 0.50 M and th
Scilla [17]

Answer:

Q = 0.50

No

Left

Explanation:

At a generic reversible equation

aA + bB ⇄ cC + dD

The reaction coefficient (Q) is the ratio of the substances concentrations:

Q = \frac{[C]^c*[D]^d}{[A]^a*[B]^b}

Solids and liquid water are not considered in this calculus.

When the reaction achieves equilibrium (concentrations are constant), the Q value is named as Kc, which is the equilibrium constant of the reaction. If Q > Kc, it indicates that the concentration of the products is higher, so, the reaction must progress to the left and form more reactants; if Q < Kc, than the concentrations of the reactants, are higher, so, the reaction progress to the right.

In this case:

Q = \frac{[NO_2]^2}{[N_2O_4]}

Q = \frac{0.50^2}{0.50}

Q = 0.50

So, Q > Kc, the reaction is not at equilibrium and it progresses to the left.

6 0
3 years ago
Draw a schematic of the hydrogen atom with the single proton in the nucleus, and the n=1, n=2, n=3, and n=4 energy level options
max2010maxim [7]

Explanation:

According to Bohr's postulates, the electron in the present in the lower energy level can absorb energy and exits to higher energy level. Also, when this electron returns back to its orbit, it emits some energy.

Since the hydrogen consists of 1 electron and 1 proton. The lowest energy configuration of the hydrogen is when n =1 or, when the electron is present in the K-shell or the ground state.

The possible transition for the electron given in the question is :

n = 2, 3 and 4

The schematic diagram of the hydrogen atom consisting of these four quantum levels in which the electron can jump (Absorption) and comeback to from these energy levels (emission) .

3 0
3 years ago
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