Express 2/10 in scientific notation

What is The most common form of matter in the universe

soldier1979 [14.2K]

Hello! My name is Zalgo and I am here to help you out today. The most common form of matter in the universe would be "Plasma". Plasma is gas that is heated a lot so it turns into high energy (high energy would be said "Plasma").

I hope that this helps! :D

"Stay Brainly and stay proud!" - Zalgo

(By the way, do you think you could mark me as Brainliest? I'd greatly appreciate it! Thanks XP)

4 0

3 years ago

How did rutherford's experimental evidence lead to the development of a new atomic number

borishaifa [10]

Rutherford's experiment was the gold foil experiment.

The gold foil experiment was him shooting alpha particles (you could think of this as a Helium atom without its electrons) into a gold foil. The whole experiment was surrounded with something called Zinc Sulfide which sparked when the alpha particles hit it.

Most of the alpha particles went through, approximately 1 in 8000 alpha particles deflected at a large angle (almost right back to where it was shot).

This constant ratio caused him to conclude that:-the atom was mostly empty space (since most alpha particles went through)-there was something very positive in the atom (the proton)-the proton was very dense (since it made something going light speed deflect back at a large angle)-The proton was also very small (since only 1 in 8000 hit it)

Prior to the discovery of the proton, John Dalton's periodic table was used. Having "elements" such as soda and potash. Now that we have discovered the proton and found out that each atom's number of protons is unique, we used that to classify each element's identity.

8 0

4 years ago

Find the enthalpy of neutralization of HCl and NaOH. 137 cm3 of 2.6 mol dm-3 hydrochloric acid was neutralized by 137 cm3 of 2.6

liraira [26]

Answer : The correct option is, (D) 89.39 KJ/mole

Explanation :

First we have to calculate the moles of HCl and NaOH.

$\text{Moles of HCl}=\text{Concentration of HCl}\times \text{Volume of solution}=2.6mole/L\times 0.137L=0.3562mole$

$\text{Moles of NaOH}=\text{Concentration of NaOH}\times \text{Volume of solution}=2.6mole/L\times 0.137L=0.3562mole$

The balanced chemical reaction will be,

$HCl+NaOH\rightarrow NaCl+H_2O$

From the balanced reaction we conclude that,

As, 1 mole of HCl neutralizes by 1 mole of NaOH

So, 0.3562 mole of HCl neutralizes by 0.3562 mole of NaOH

Thus, the number of neutralized moles = 0.3562 mole

Now we have to calculate the mass of water.

As we know that the density of water is 1 g/ml. So, the mass of water will be:

The volume of water = $137ml+137ml=274ml$

$\text{Mass of water}=\text{Density of water}\times \text{Volume of water}=1g/ml\times 274ml=274g$

Now we have to calculate the heat absorbed during the reaction.

$q=m\times c\times (T_{final}-T_{initial})$

where,

q = heat absorbed = ?

$c$ = specific heat of water = $4.18J/g^oC$

m = mass of water = 274 g

$T_{final}$ = final temperature of water = 325.8 K

$T_{initial}$ = initial temperature of metal = 298 K

Now put all the given values in the above formula, we get:

$q=274g\times 4.18J/g^oC\times (325.8-298)K$

$q=31839.896J=31.84KJ$

Thus, the heat released during the neutralization = -31.84 KJ

Now we have to calculate the enthalpy of neutralization.

$\Delta H=\frac{q}{n}$

where,

$\Delta H$ = enthalpy of neutralization = ?

q = heat released = -31.84 KJ

n = number of moles used in neutralization = 0.3562 mole

$\Delta H=\frac{-31.84KJ}{0.3562mole}=-89.39KJ/mole$

The negative sign indicate the heat released during the reaction.

Therefore, the enthalpy of neutralization is, 89.39 KJ/mole

3 0

4 years ago

If not as an element, atoms show up as _______________ and _______________

enot [183]

Answer:

greater or less

mass/ grams

atom/ mass

8 0

4 years ago

Sam and Joe are trying to determine whether their ideas are scientific or pseudoscientific. Sam's idea is not rejected when expe

xenn [34]

Answer:

See the complete question and the answer below

Explanation:

Sam and joe are trying to determine whether their ideas are scientific or pseudoscientific. sam's idea is not rejected when experiments produce different results. joe's idea gives the same result when tested repeatedly. which statement is correct about sam and joe's idea?

both ideas could be scientific.

neither idea could be scientific.

only sam's idea could be scientific.

only joe's idea could be scientific.

The correct answer here would be that both ideas could scientific.

Scientific ideas are those that hold true or not rejected after being tested by different experiments. Pseudoscientific ideas cannot hold true after being tested by experiments.

If an idea is tested by repeated experiments and the experiments produce different results, the idea might remain unrejected if there are no overwhelming evidence to do so from the experiments. That an idea remains unrejected due to inadequate experimental evidence, however, does not mean it is scientific or unscientific.

In the same vein, that a repeatedly tested idea gives the same results does not mean that the idea is scientific unless the results say so. If results repeatedly go against the idea, it means such an idea is unscientific or pseudoscientific.

Hence, both Joe and Sam's idea could be scientific, provided further experimental investigations are carried out.

3 0

4 years ago