7th grade science can anyone help

A motorcycle travel at 6.0 m/s. After 3.0 second, the motorcycle travel at 15.0 m/s. Which of the following was the average acce

Lerok [7]

Hello!

$\large\boxed{a = 3m/s^{2}}$

Use the following equation to solve for the average acceleration of the motorcycle:

$a = \frac{v_{f}-v_{i}}{t}$

Plug in the given final, initial velocities, and the time:

$a = \frac{15-6}{3}\\\\a = \frac{9}{3}\\\\a = 3m/s^{2}$

7 0

2 years ago

What was the plum pudding atomic model

postnew [5]

Thomson's atomic model is a theory about the atomic structure proposed in 1904 by Thomson, who discovered the electron in 1897, a few years before the discovery of the proton and the neutron.

Hope this helps :))

3 0

2 years ago

Read 2 more answers

The density of an aqueous solution of nitric acid is 1.64 g/mL and the concentration is 1.85 M. What is the concentration of thi

galina1969 [7]

Answer:

Mass % of the solution = 7.1067 %

Explanation:

Given :

Molarity of nitric acid solution = 1.85 M

Density of the solution = 1.64 g/mL

Molarity of a solution is defined as the number of moles of solute present in 1 liter of the solution.

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

Lets, consider the volume of the solution = 1 L

Thus,

Moles of nitric acid present in the solution:

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

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

So,

Moles of Nitric acid = 1.85 moles

Molar mass of nitric acid = 63 g/mol

The mass of Nitric acid can be find out by using mole formula as:

$moles=\frac{Mass\ taken}{Molar\ mass}$

Thus,

$Mass\ of\ Nitric\ acid=Moles \times Molar mass}$

$Mass\ of\ Nitric\ acid=1.85 g \times 63 g/mol}$

Mass of Nitric acid = 116.55 g

Also,

$Density=\frac{Mass}{Volume}$

Given : Density = 1.64 g/mL

Also, 1 L = 10³ mL

Volume of the solution is 1000 mL

So, mass of the solution:

$Mass\ of\ the\ solution=Density \times {Volume\ of\ the\ solution}$

$Mass\ of\ the\ solution=1.64 g/mL \times {1000 mL}$

Mass of the solution = 1640 g

Mass % is defined as the mass of solute in 100 g of the solution. The formula for the calculation of mass % is shown below:

$Mass \% =\frac{Mass\ of\ the\ solute}{Mass\ of\ the\ solution} \times {100}$

So,

$Mass \%=\frac{116.55}{1640} \times {100}$

Mass % = 7.1067 %

6 0

2 years ago

If a 1000. ml of linseed oil has a mass of 929 g, what is the density of the oil

uysha [10]

$Formula\ for\ density:\\\\
density=\frac{mass}{volume}\\\\
mass=929g=0,929kg\\\\
volume=1000ml=0,001m^3\\\\
denisty=\frac{0,929kg}{0,001m^3}=
\boxed{929\frac{kg}{m^3}}$

5 0

2 years ago

Magnesium acetate can be prepared by a reaction involving 15.0 grams of iron(III) acetate with either 10.0 grams of Magnesium Ch

noname [10]

1) Chemical reaction:
2(CH₃COO)₃Fe + 3MgCrO₄ → Fe₂(CrO₄)₃ + 3(CH₃COO)₂Mg.
m((CH₃COO)₃Fe) = 15,0 g.
m(MgCrO₄) = 10,0 g.
n((CH₃COO)₃Fe) = m((CH₃COO)₃Fe) ÷ M((CH₃COO)₃Fe).
n((CH₃COO)₃Fe) = 15 g ÷ 233 g/mol.
n((CH₃COO)₃Fe) = 0,064 mol.
n(MgCrO₄) = m(MgCrO₄) ÷ M(MgCrO₄).
n(MgCrO₄) = 10 g ÷ 140,3 g/mol.
n(MgCrO₄) = 0,071 mol; limiting reagens.
From chemical reaction: n(MgCrO₄) : n((CH₃COO)₂Mg) = 3 : 3.
n((CH₃COO)₂Mg) = 0,071 mol.
m((CH₃COO)₂Mg) = 0,071 mol · 142,4 g/mol.
n((CH₃COO)₂Mg) = 10,11 g.

2) Chemical reaction:
2(CH₃COO)₃Fe + 3MgSO₄ → Fe₂(SO₄)₃ + 3(CH₃COO)₂Mg.
m((CH₃COO)₃Fe) = 15,0 g.
m(MgSO₄) = 15,0 g.
n((CH₃COO)₃Fe) = m((CH₃COO)₃Fe) ÷ M((CH₃COO)₃Fe).
n((CH₃COO)₃Fe) = 15 g ÷ 233 g/mol.
n((CH₃COO)₃Fe) = 0,064 mol; limiting ragens.
n(MgSO₄) = m(MgSO₄) ÷ M(MgSO₄).
n(MgSO₄) = 15 g ÷ 120,36 g/mol.
n(MgSO₄) = 0,125 mol; limiting reagens.
From chemical reaction: n(CH₃COO)₃Fe) : n((CH₃COO)₂Mg) = 2 : 3.
n((CH₃COO)₂Mg) = 0,064 mol · 3/2.
n((CH₃COO)₂Mg) = 0,096 mol.
m((CH₃COO)₂Mg) = 0,096 mol · 142,4 g/mol.
m((CH₃COO)₂Mg) = 13,7 g.

7 0

2 years ago