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3 years ago

I need an answer asap

Chemistry

1 answer:

Levart [38]3 years ago

7 0

Scientists can calculate the number of neutrons by subtracting the atomic number from the atomic mass.

they subtract the protons

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What is the electron configuration for Ba

babunello [35]

Full electron configuration of barium: 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 6s2

8 0

3 years ago

A student has four resistors. Each resistor has a resistance of 100 ohms.

ValentinkaMS [17]

Answer:

The minimum resistance is 25 ohms.

Explanation:

Resistance of each resistor is 100 ohms. When resistors are connected in parallel, the equivalent resistance is lowest. For parallel combination, the equivalent resistance is given by :

$\dfrac{1}{R}=\dfrac{1}{R_1}+\dfrac{1}{R_2}+....$

Here, all resistors are 100 ohms. So,

$\dfrac{1}{R}=\dfrac{1}{100}+\dfrac{1}{100}+\dfrac{1}{100}+\dfrac{1}{100}\\\\R=25\ \Omega$

So, the minimum resistance is 25 ohms.

7 0

3 years ago

New questionWhat mass of calcium chloride (CaCl₂) would beproduced from the reaction of 125.9 g of hydrochloriacid (HCI) with ex

marshall27 [118]

Answer:

191.6 g of CaCl₂.

Explanation:

What is given?

Mass of HCl = 125.9 g.

Molar mass of CaCl₂ = 110.8 g/mol.

Molar mass of HCl = 36.4 g/mol.

Step-by-step solution:

First, we have to state the chemical equation. Ca(OH)₂ react with HCl to produce CaCl₂:

$Ca(OH)_2+2HCl\rightarrow CaCl_2+2H_2O.$

Now, let's convert 125.9 g of HCl to moles using the given molar mass (remember that the molar mass of a compound can be found using the periodic table). The conversion will look like this:

$125.9\text{ g HCl}\cdot\frac{1\text{ mol HCl}}{36.4\text{ g HCl}}=3.459\text{ moles HCl.}$

Let's find how many moles of CaCl₂ are being produced by 3.459 moles of HCl. You can see in the chemical equation that 2 moles of HCl reacted with excess Ca(OH)₂ produces 1 mol of CaCl₂, so we state a rule of three and the calculation is:

$3.459\text{ moles HCl}\cdot\frac{1\text{ mol CaCl}_2}{2\text{ moles HCl}}=1.729\text{ moles CaCl}_2.$

The final step is to find the mass of CaCl₂ using the molar mass of CaCl₂. This conversion will look like this:

$1.729\text{ moles CaCl}_2\cdot\frac{110.8\text{ g CaCl}_2}{1\text{ mol CaCl}_2}=191.6\text{ g CaCl}_2.$

The answer would be that we're producing a mass of 191.6 g of CaCl₂.

4 0

1 year ago

Type the correct answer in each box.

Arturiano [62]

Answer:

5SiO2 + 2CaC2 = 5Si + 2CaO + 4CO2

Explanation:

balancing equations is a lot of trial and error. My strategy to approaching this equation was to get the O's balanced. After trying several combonations I found that I needed 10 O's on each side of the equation for the other elements to match up. After I balanced the O's, I balanced my C's to 4 on each side. Then I balanced my Ca's to have 2 on each side. And last but not least I balanced my Si to have 5 on each side.

8 0

3 years ago

I need to find the chemical equation

Yuri [45]

Answer:

2NaCN + CaCO3 --> Na2CO3 + Ca(CN)2

Explanation:

Knowing the names gets us: NaCN + CaCO3 --> Na2CO3 + Ca(CN)2

Balance: there are two sodiums and cyanides on the product side so add a 2 to the reactant side.

4 0

3 years ago