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3 years ago

Which of the following does not indicate a chemical change?

1 answer:

6 0

I believe the correct answer is the second option. It is crushing a solid into a powder that does not indicate a chemical change. A chemical change is a change of a substance into another substance with another set of properties. Crushing does not change a substance properties so it is only a physical change.

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a baseball player hits a baseball with a bat.The mass of the ball is 0.25kg.The ball accelerates at 200m/s2

34kurt

Answer:

50N

Explanation:

Force (N) = mass (kg) × acceleration (m/s²)

0.25kg times 200m/s² = 50N

5 0

3 years ago

Which solution has the highest boiling point at standard pressure?

artcher [175]

The correct answer is 3: 0.10 M K3PO4(aq). The higher the concentration (or molarity), the higher the boiling point. Thus, the solution with the most moles will have the highest boiling point. SO4, PO4, and NO3 are all polyatomic ions, so by definition, they only have one mole. In K3PO4, K3 has 3 moles and PO4 has 1 mole, meaning all together it has 4 moles (more than any of the other options).

6 0

3 years ago

The lewis representation above depicts a reaction between hydrogen (blue) and a main-group element from group (red). in this rep

Fed [463]

The question is incomplete, the complete question is;

The Lewis representation above depicts a reaction between hydrogen (blue) and a main-group element from group______ (red).

In this representation, each Y atom needs ______ electron(s) to complete its octet, and gains these electrons by forming______ bond(s) with atoms of H .

There are ______ unshared electron pair(s) and _______bonding electron pair(s) in the product molecule.

The bonds in the product are _________ (Ionic or Covalent)

Answer:

1) 16

2) 2 electrons

3) 2 bonds

4) 2 unshared pairs of electrons

5) 2 bonding pairs of electrons

6) The bonds in the product are covalent

Explanation:

Group sixteen elements have six electrons on their outermost shell. These include two unshared pairs of electrons and two unpaired electrons. These two unpaired electrons can now be covalently bonded to two hydrogen atoms to give H2Y. The compound H2Y has two lone pairs and two bond pairs of electrons.

H2Y can be a general formula for all hydrides of group 16. They are all very similar in structure but gradually differ in physical and chemical properties according to the graduated variation observed down the group.

6 0

3 years ago

Be sure to answer all parts. Nitric oxide (NO) reacts with oxygen gas to form nitrogen dioxide (NO2), a dark brown gas: 2NO(g) +

notka56 [123]

Answer: NO is the limiting reagent in the given reaction and 0.857 moles of $NO_2$ will be produced.

Explanation:

Limiting reagent is defined as the reagent which is present in less amount and it limits the formation of products.

Excess reagent is defined as the reagent which is present in large amount.

For the given chemical reaction:

$2NO(g)+O_2(g)\rightarrow 2NO_2(g)$

We are given:

Moles of NO = 0.857 mol

Moles of oxygen = 0.498 mol

By stoichiometry of the reaction:

If 2 moles of NO reacts with 1 mole of oxygen gas.

So, 0.857 moles of NO will react with = $\frac{1}{2}\times 0.857=0.4285mol$ of $O_2$

As, the given amount of oxygen gas is more than the required amount. So, it is considered as an excess reagent.

Thus, NO is considered as the limiting reagent because it limits the formation of products.

By Stoichiometry of the reaction:

If 2 moles of NO produces 2 moles of nitrogen dioxide gas.

So, 0.857 moles of NO will produce = $\frac{2}{2}\times 0.857=0.857mol$ of $NO_2$

Hence, NO is the limiting reagent in the given reaction and 0.857 moles of $NO_2$ will be produced.

6 0

3 years ago

Create an element card that has the following information:

Shtirlitz [24]

Answer:

Atomic number:6

Atomic mass:12.011

Chemical symbol:C

Name of element: Carbon, Carbone (french)

Image is in my explanation

Explanation:

6 0

3 years ago