A(n) ____ is an abbreviation for the name of an element and has either one or two letters.

SOVA2 [1]

Answer:

They all have the same number of protons but different numbers of neutrons.

Explanation:

Elements will always have the same number of protons no matter the isotopes. Isotopes only change the number of neutrons. Silicon will always have 14 protons. So silicon-28 has 14 protons and 14 neutrons. Silicon-29 has 14 protons and 15 neutrons. Silicon-30 has 14 protons and 16 neutrons.

8 0

4 years ago

What is the difference between an imprint and an impression?

liubo4ka [24]

Answer:

As nouns the difference between impression and imprint

is that impression is the indentation or depression made by the pressure of one object on or into another while imprint is an impression; the mark left behind by printing something.

5 0

3 years ago

in an experiment 3.425g of lead oxide was reduced to form 3.105g of lead the empirical formula of the lead oxide is?

Romashka-Z-Leto [24]

Answer:

Pb3O4

Explanation:

According to this question, 3.425g of lead oxide was reduced to form 3.105g of lead in an experiment. Since lead oxide contains both lead (Pb) and oxygen (O) element,

Mass of lead oxide = 3.425g

Mass of lead = 3.105g

Mass of oxygen = (3.425g - 3.105g) = 0.320g

Next, we convert each mass value to mole by dividing by respective molar mass

Pb = 3.105g ÷ 207.2 = 0.0149mol

O = 0.320g ÷ 16 = 0.02mol

Next, we divide each mole value by the smallest (0.0149)

Pb = 0.0149mol ÷ 0.0149mol = 1

O = 0.02mol ÷ 0.0149mol = 1.342

Multiply each ratio value by 3 to get:

Pb = 1 × 3 = 3

O = 1.342 × 3 = 4.026

The whole number ratio, approximately, of Pb and O is 3:4, hence, their empirical formula is Pb3O4.

4 0

3 years ago

12. If a solution has a pH of 3, what would the pOH value of that solution be? *

butalik [34]

Answer:

The correct answer is pOH= 11

Explanation:

From the aqueous acid-base equilibrium we know that

pH + pOH = 14

If we know pH, we can calculate pOH as follows:

pOH = 14 - pH

In this problem, the solution has a pH of 3, so:

pOH = 14 - 3 = 11

8 0

3 years ago

Read 2 more answers

At equilibrium at 2500K, [HCl]=0.0625M and [H2]=[Cl2]=0.00450M for the reaction H2+Cl2 ⇌ HCl.

ASHA 777 [7]

Answer:

a. $H_2+Cl_2 \rightleftharpoons 2HCl$

b. K = 192.9

c. Products are favored.

Explanation:

Hello!

a. In this case, according to the unbalanced chemical reaction we need to balance HCl as shown below:

$H_2+Cl_2 \rightleftharpoons 2HCl$

In order to reach 2 hydrogen and chlorine atoms at both sides.

b. Here, given the concentrations at equilibrium and the following equilibrium expression, we have:

$K=\frac{[HCl]^2}{[H_2][Cl_2]}$

Therefore, we plug in the data to obtain:

$K=\frac{(0.0625)^2}{(0.00450)(0.00450)}\\\\K=192.9$

c. Finally, we infer that since K>>1 the forward reaction towards products is favored.

Best regards!

8 0

3 years ago