Online class this is my TEACHER

mixture or pure substance: 1.blood 2.dyes 3.self-raising flour 4.muesli 5.copper wire 6.distilled water 7.table salt 8.milk 9.br

jenyasd209 [6]

Answer: Mixture: Blood , Self raising flour,muesli ,dyes, milk, tea, air, bronze

Pure substance: Copper wire, distilled water, table salt, oxygen.

Explanation:

Mixture is a substance which is made up two or more number of compounds which chemically inactive and retain their distinct chemical properties.

Blood , Self raising flour,muesli ,dyes, milk, tea, air, bronze

Pure substance is defined as anything with uniform and unchanging composition is known s pure substance.

Copper wire, distilled water, table salt, oxygen.

5 0

3 years ago

Read the given expression. X = number of protons − number of core electrons Which of the following explains the identity of X an

shepuryov [24]

<u>Answer: </u>The correct statement is X is the effective nuclear charge, and it increases across a period.

<u>Explanation:</u>

We are given that:

X = number of protons − number of core electrons

Effective nuclear charge is defined as the actual nuclear charge (Z = number of protons) minus the screening effect caused by the electrons present between nucleus and valence electrons. These electrons are the core electrons.

The formula used for the calculation of effective nuclear charge given by Slater is:

$Z^*=Z-\sigma$

where,

$Z^*$ = effective nuclear charge

Z = atomic number or actual nuclear charge or number of protons

$\sigma$ = Screening constant

The effective nuclear charge increases as we go from left to right in a period because nuclear charge increases with no effective increase in screening constant.

Hence, the correct answer is X is the effective nuclear charge, and it increases across a period.

5 0

4 years ago

The formula for Na2 O

Rudiy27

Answer:

Na₂O is the formula for the ionic compound "sodium oxide".

It has 2 sodium atoms and 1 oxygen atom.

The number of atoms for an element are written as a subscript after the element. "1" subscripts are not written.

The names of the elements are found on the periodic table.

8 0

3 years ago

Read 2 more answers

Compare the state of plasma to the other states of matter

dmitriy555 [2]

Plasma is the most least form on Earth and we hardly use it but it is the most common in the universe because it is mostly loacted in space

4 0

4 years ago

Ammonia gas and oxygen gas react to form water vapor and nitrogen monoxide gas. What volume of water would be produced by this r

NikAS [45]

Answer:

Water volume produced is 7.3 mL

Explanation:

This the reaction:

4NH₃ (g) + 5O₂ (g) → 4NO (g) + 6H₂O (g)

We have to work with density, to solve this question

Density of ammonia = Ammonia mass / Ammonia volume

0,00073 g/mL = Ammonia mass / 6300 mL

(Notice, we had to convert 6.3L to mL)

0.00073 g/mL . 6300 mL = Ammonia mass → 4.599 g

Mass / Molar mass = Mol

4.599 g / 17g/m = 0.270 mole

Ratio is 4:6

4 mole of ammonia produce 6 mole of water

0.270 mole produce (0.270 .6)/4 = 0.405 mol

Molar mass . mole = mass

18 g/m . 0.405 m = 7.30 g

Water density = 1 g/mL

Water density = Water mass / Water Volume

1g/mL = 7.30 g / Water volume

Water volume = 7.3 mL

5 0

3 years ago

Online class this is my TEACHER ​

Online class this is my TEACHER