A certain atom has 26 protons 26 electrons and 30 neutrons. its mass number is

A chemistry teacher is able to grade chemistry labs at a rate of 5 labs for every 3 minutes. They need to grade 165 labs how man

PIT_PIT [208]

Answer:

1.65hr

Explanation:

Given parameters:

Number of labs = 5 labs

Time taken = 3 minutes

Unknown:

Time taken in hours to grade 165 labs = ?

Solution:

Let us find the rate of the teacher;

Rate = $\frac{number of labs}{time}$

Insert the parameters and solve;

Rate = $\frac{5}{3}$ = 1.67labs/min

Now;

Time to grade 165 labs = $\frac{number of labs}{rate}$

Time to grade 165 labs = $\frac{165}{1.67}$ = 98.8min

Since;

60min = 1hr

98.8min = $\frac{98.8}{60}$ = 1.65hr

3 0

3 years ago

After measuring the mass of water, the data is averaged and it is determined that the mean of 4

gladu [14]

Answer:

2

Explanation:

8 0

3 years ago

if the Earth were to begin to enter another ice age, which of the following characteristics might help an animal survive?

Stolb23 [73]

Not sure but i think living things adapt to their environment.
Adaptations are traits giving an organism an advantage in a certain environment. And variations of individuals is important for a healthy species. So i think adaptation might be the right answer because animal will try to adapt the certain environment. I hope this answer will help you.

5 0

3 years ago

) Consider the starting materials and reagents. What do you expect to happen at the beginning of this reaction (Boxes 1-3 on the

tekilochka [14]

Answer:

Check the explanation

Explanation:

functional group found in the major organic product = alpha -beta unsaturated ketone

Reaction used to form this functional group = Michael condensation reaction

Also other reactions are - Aldol condensation , Robinson annulation reaction.

Kindly check the attached image below to see the step by step solution to the question above.

3 0

3 years ago

The halogens, the elements of Family 17 on the periodic table, combine easily with elements from Family 1. When a halogen reacts

timofeeve [1]

Answer:

When halogen elements react with group one metals they form halide salts.

Explanation:

The elements of group 17 are called halogens. These are six elements Fluorine, Chlorine, Bromine, Iodine, Astatine. Halogens are very reactive these elements can not be found free in nature. Their chemical properties are resemble greatly with each other. As we move down the group in periodic table size of halogens increases that's way fluorine is smaller in size as compared to other halogens elements. Their boiling points also increases down the group which changes their physical states. i.e fluorine is gas while iodine is solid.

When halogen elements react with group one metals they form halide salts.

Alkali metals have one valance electron and halogens needed one electron to complete the octet thus alkali metals loses one electron which is accepted by halogens atom and form ionic compound called halide salts.

For example:

2Na + Cl₂ → 2NaCl

2K + Cl₂ → 2KCl

2Rb + Cl₂ → 2RbCl

2Li + Cl₂ → 2LiCl

With bromine:

2Na + Br₂ → 2NaBr

2K + Br₂ → 2KBr

2Rb + Br₂ → 2RbBr

2Li + Br₂ → 2LiBr

With iodine:

2Na + I₂ → 2NaI

2K + I₂ → 2KBI

2Rb + I₂ → 2RbI

2Li + I₂ → 2LiI

4 0

3 years ago