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3 years ago

8

I’m lost for this question

1 answer:

Natasha2012 [34]3 years ago

7 0

An element is all the same thing. Pure, if you will.

The first one is definitely an element. The second would be a compound (it's atoms are different colors). I would say the last one is an element, since it has ll the same color of atoms.

I hope this helped you! If you have anymore questions, feel free to ask me.

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Magnesium is an active metal; it burns in the form of powder, ribbons, and filaments to

dolphi86 [110]

Explanation:

magnesium can be used for the construction as only when the metal is divided into fine pieces or as a thin sheet, magnesium will burn rapidy.

5 0

3 years ago

g The first step in the process is to calibrate the grating, so we know the grating spacing (the distance between the openings i

Trava [24]

Answer:

The grating spacing is $d = 1055nm$

Explanation:

From the question we are told that

The wavelength is $\lambda = 590 nm = 590 *10^{-9}m$

The angle is $\theta = 34^0$

The order of the spectrum is $n = 1$

Generally in grating grating the condition for maxima to occur is

$d sin \theta = n \lambda$

where d is the grating spacing

making d the subject of the formula

$d = \frac{\lambda }{sin \theta }$

Substituting values

$d = \frac{590 * 10^{-9}}{sin (34)}$

$d = 1055nm$

8 0

3 years ago

Given the balanced equation representing a reaction:

Nesterboy [21]

Answer:

It accepted a proton from HCl

Explanation:

When properly written, the equation box the reaction is given as; HCl(aq) + H2O(l) ----> H3O+(aq) + Cl-(aq).

According to Brownstead-Lowry definition of acids and bases, an acid donates protons while a base accepts protons.

Water molecule acts as a base in the reaction because it accepted a proton from HCl in the reaction above.

7 0

3 years ago

I need help answering 14 and 15

Debora [2.8K]

Answer:

14 is D and 15 is C

Explanation:

4 0

4 years ago

2. Suppose that 21.37 mL of NaOH is needed to titrate 10.00 mL of 0.1450 M H2SO4 solution.

AysviL [449]

Answer:

0.1357 M

Explanation:

(a) The balanced reaction is shown below as:

$2NaOH+H_2SO_4\rightarrow Na_2SO_4+2H_2O$

(b) Moles of $H_2SO_4$ can be calculated as:

$Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}$

Or,

$Moles =Molarity \times {Volume\ of\ the\ solution}$

Given :

For $H_2SO_4$ :

Molarity = 0.1450 M

Volume = 10.00 mL

The conversion of mL to L is shown below:

1 mL = 10⁻³ L

Thus, volume = 10×10⁻³ L

Thus, moles of $H_2SO_4$ :

$Moles=0.1450 \times {10\times 10^{-3}}\ moles$

Moles of $H_2SO_4$ = 0.00145 moles

From the reaction,

1 mole of $H_2SO_4$ react with 2 moles of NaOH

0.00145 mole of $H_2SO_4$ react with 2*0.00145 mole of NaOH

Moles of NaOH = 0.0029 moles

Volume = 21.37 mL = 21.37×10⁻³ L

Molarity = Moles / Volume = 0.0029 / 21.37×10⁻³ M = 0.1357 M

7 0

3 years ago