ASAP (2 questions & are iv the pic ) will get BRAINIEST

What is the solution to the problem expressed to the correct number of significant figures 102900/12 +170•1.27

Morgarella [4.7K]

The solution to the problem (102 900 ÷ 12) + (170 × 1.27) = 8800.

Explanation:

Step 1.

Evaluate the expressions inside the parentheses (PEMDAS)

102 900 ÷ 12 = 8575

170 × 1.27 = 215.9

In multiplication and division problems, your answer can have no more significant figures than the number with the fewest significant figures.

Thus, the underlined digits are not significant, but we keep them in our calculator to avoid roundoff error.

Step 2.

Do the addition (PEMDAS).

8575 + 215.9 = 8790.9

Everything that you add to an insignificant digit gives an insignificant digit as an answer.

Thus, the underlined digits are not significant.

We must drop them and round up the answer to 8800.

4 0

4 years ago

Read 2 more answers

Given: 36.7 grams of CaF2 is added to 300 mL water. Find molarity?

BigorU [14]

<h3>Answer:</h3>

2 M

<h3>General Formulas and Concepts:</h3>

Math

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Chemistry

Unit 0

Reading a Periodic Table
Using Dimensional Analysis

Aqueous Solutions

Molarity = moles of solute / liters of solution

<h3>Explanation:</h3>

Step 1: Define

36.7 g CaF₂

300 mL H₂O

Step 2: Identify Conversions

Molar Mass of Ca - 40.08 g/mol

Molar Mass of F - 19.00 g/mol

Molar Mass of CaF₂ - 40.08 + 2(19.00) = 78.08 g/mol

1000 mL = 1 L

Step 3: Convert

Solute

Set up: $\displaystyle 36.7 \ g \ CaF_2(\frac{1 \ mol \ CaF_2}{78.08 \ g \ CaF_2})$
Multiply: $\displaystyle 0.470031 \ mol \ CaF_2$

Solution

Set up: $\displaystyle 300 \ mL \ H_2O(\frac{1 \ L \ H_2O}{1000 \ mL \ H_2O})$
Multiply: $\displaystyle 0.3 \ L \ H_2O$

Step 4: Find Molarity

Substitute [M]: $\displaystyle x \ M = \frac{0.470031 \ mol \ CaF_2}{.3 \ L \ H_2O}$
Divide: $\displaystyle x = 1.56677 \ M$

Step 5: Check

Follow sig fig rules and round. We are given 1 sig fig as our lowest.

1.56677 M ≈ 2 M

8 0

3 years ago

Explain and illustrate the notation for distinguishing between the different p orbitals in a sublevel.

masha68 [24]

Here, the three different notation of the p-orbital in different sub-level have to generate

The value of azimuthal quantum number (l) for -p orbital is 1. We know that the magnetic quantum number $m_{l}$ depends upon the value of l, which are -l to +l.

Thus for p-orbital the possible magnetic quantum numbers are- -1, 0, +1. So there will be three orbitals for p orbitals, which are designated as $p_{x}$ , $p_{y}$ and $p_{z}$ in space.

The three p-orbital can be distinguish by the quantum numbers as-

For 2p orbitals (principal quantum number is 2)

1) n = 2, l = 1, m = -1

2) n = 2, l = 1, m = 0

3) n = 2, l = 1, m = +1

Thus the notation of different p-orbitals in the sub level are determined.

6 0

3 years ago

What is the concentration of the hydroxide ion? Given that the concentration of the hydronium ion is 2.3 X 10^-7 M

professor190 [17]

Answer:

4.35 * 10^-8 M

Explanation:

Since the concentration of the hydronium ion= 2.3 X 10^-7 M

And we know that;

[H3O^+] [OH^-] = 1 * 10^-14

[H3O^+] = concentration of the hydronium ion

[OH^-] = concentration of the hydroxide ion

So;

[OH^-] =1 * 10^-14/[ H3O^+]

But [H3O^+] = 2.3 X 10^-7 M

[OH^-] = 1 * 10^-14/2.3 X 10^-7

[OH^-] = 4.35 * 10^-8 M

8 0

3 years ago

Determine the number of valence electrons in pcl₃ and then draw the corresponding lewis structure.

Nikolay [14]

The number of valence electrons in $PCl_{5}$ will be 26.

The atom's outermost inhabited shell is where valence electrons are found. They are significant because they have a major impact on how an atom's chemical characteristics are determined.

The number of valence electron in P in 5 and number of valence electron in Cl is 7. There are one molecule of P and three molecule of Cl in $PCl_{5}$ molecule. By adding all valence electrons , the total number of valance electrons will be 26.

The Lewis structure of $PCl_{5}$ is shown as:

Therefore, the number of valence electrons in $PCl_{5}$ will be 26.

To know more about valence electrons

brainly.com/question/13993867

#SPJ4

7 0

2 years ago