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2 years ago

17.The column that an element is located in tells us

Chemistry

1 answer:

krok68 [10]2 years ago

4 0

Answer:

A. the total number of valence electrons an atom has.

Explanation:

The columns on the periodic table are called groups or families because of their similar chemical behavior. All the members of a family of elements have the same number of valence electrons and similar chemical properties.

You might be interested in

Name each subatomic particle, its charge, and its location in an atom.

Tpy6a [65]

Protons: charge +1, have a mass of 1 and are found in the nucleus

Neutrons: charge 0, have a mass of 1 and are found in the nucleus

Electrons: charge -1, have a mass of 1/840 and are found on the outside of the nucleus

hope that helps

4 0

2 years ago

12.5 mL of 0.280 M HNO3 and 5.0 mL of 0.920 M KOH are mixed. Is the resulting solution acidic, basic or neutral?

svlad2 [7]

Answer:

The resulting solution is basic.

Explanation:

The reaction that takes place is:

HNO₃ + KOH → KNO₃ + H₂O

First we <u>calculate the added moles of HNO₃ and KOH</u>:

HNO₃ ⇒ 12.5 mL * 0.280 M = 3.5 mmol HNO₃

KOH ⇒ 5.0 mL * 0.920 M = 4.6 mmol KOH

As <em>there are more KOH moles than HNO₃,</em> the resulting solution is basic.

8 0

2 years ago

What is the standard enthalpy of a reaction for which the equilibrium constant is (a) doubled, (b) halved when the temperature i

Alexxandr [17]

Answer:

a) 48KJ

b) -48KJ

Explanation:

Given that;

ln(K2/K1) = ΔH°/R(1/T2 - 1/T1)

K2= equilibrium constant at T2

K1 = equilibrum constant at T1

R = gas constant

T1 = initial temperature

T2 = final temperature

When we double the equilibrium constant K1; K2 = 2K1

T1 = 310 K

T2 = 310 + 15 = 325 K

ln(2K1/K1) =- ΔH°/R(1/T2 - 1/T1)

ln2 = -ΔH°/8.314(1/325 - 1/310)

0.693 = -ΔH°/8.314(3.08 * 10^-3 - 3.2 * 10^-3)

0.693 = -ΔH°/8.314 (-0.00012)

0.693 = 0.00012ΔH°/8.314

0.693 * 8.314 = 0.00012ΔH°

ΔH° = 0.693 * 8.314/0.00012

ΔH° = 48KJ

b) K2 =K1/2

ln(K1/2/K1) =- ΔH°/R(1/T2 - 1/T1)

ln (1/2) = -ΔH°/8.314 (1/325 - 1/310)

-0.693 = -ΔH°/8.314 (-0.00012)

-0.693 = 0.00012ΔH°/8.314

-0.693 * 8.314 = 0.00012ΔH°

ΔH°= -0.693 * 8.314/0.00012

ΔH°= -48KJ

6 0

3 years ago

How can you compare the DNA in your brain cells to the DNA in your heart cells ?

alekssr [168]

The DNA is identical because all of your cells came from that one cell through mitosis which gives and exact copy of the DNA. All body cells got the complete "instruction manual" for the body, but only uses the proteins needed.

8 0

3 years ago

Describe how you could use two LB/agar plates, some E. coli, and some ampicillin to determine how E. coli cells are affected by

KiRa [710]

Answer:

For this experiment we are going to take plate 1 as the control plate, so, in it there will be just E. coli in LB/agar; in plate 2, we are going to put E. coli in LB/agar and some ampicillin. Then, we have to wait for the E. coli colonies to form. After a while, the E. coli growth can be compared on both plates and determine if ampicillin affects or not the E. coli colonies.

Explanation:

If the ampicillin affects negatively E. coli colonies, we are going to observe that in plate 1 (control plate) there are E. coli colonies growing, but in plate 2, there is no E. coli colonies or, at least, there is a fewer number of colonies on it. If ampicillin doesn't affect E.coli, plate 1 (control) and plate 2 (ampicillin experiment) are going to be similar in number of colonies.

8 0

3 years ago