Answer:
The result is 3.859 in which we use four significant figures.
Explanation:
We start by solving the mathematical operation :
The result for the operation is 3.859438 but the numbers in the operation are given with four significant figures and that is why we are going to use four significant figures to express the result
To express 3.859438 with four significant figures we use the first four digits that appear from left to right starting by the first digit that is different to zero
In this case : 3.859 will be the result with four significant figures.
We also use a rule that says : To decide if the last significant figure remains the same we look for the value of the digit at its right.
If that number is greater than or equal to 5 ⇒ we sum one to the last significant figure
For example 3.859738 = 3.860 with four significant figures because the ''7'' is greater that 5
If that number is less than 5 ⇒ the last significant figure remains the same
In our case : 3.859438 = 3.859 because ''4'' is less than ''5''
The density of the gas is 1.45 g/L.
The mass of the gas is 0.0707 g.
The volume of the gas is 48.9 mL.
Density = mass/volume = 0.0707 g/48.9 mL = 1.45 × 10⁻³ g/mL = 1.45 g/L
It gives each organelle in the cell its own specific function
Answer : The correct option is A.
Explanation :
Law of conservation of mass : In the chemical reaction, the mass of reactant must be equal to the mass of product.
A. 
The mass of reactant side = ![2C_4H_{10}+2Cl_2+12O_2=[8(12)+20(1)]+4(35.5)+24(16)=642g](https://tex.z-dn.net/?f=2C_4H_%7B10%7D%2B2Cl_2%2B12O_2%3D%5B8%2812%29%2B20%281%29%5D%2B4%2835.5%29%2B24%2816%29%3D642g)
The mass of product side = 
This means, the mass of product is equal to the mass of reactant. The mass remains conserved and obeys the law of conservation of mass.
The reaction B, C, D, E does not obey the law of conservation of mass.
Therefore, Only reaction A obey the law of conservation of mass.
Answer:
Net ionic equation:
Ba²⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)
Explanation:
Chemical equation:
BaCl₂ + Na₂SO₄ → BaSO₄ + NaCl
Balanced Chemical equation:
BaCl₂(aq) + Na₂SO₄(aq) → BaSO₄(s) + 2NaCl(aq)
Ionic equation:
Ba²⁺(aq) + 2Cl⁻(aq) + 2Na⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)+ 2Na⁺(aq) + 2Cl⁻ (aq)
Net ionic equation:
Ba²⁺(aq) + SO₄²⁻(aq) → BaSO₄(s)
The Cl⁻(aq) and Na⁺ (aq) are spectator ions that's why these are not written in net ionic equation. The BaSO₄ can not be splitted into ions because it is present in solid form.
Spectator ions:
These ions are same in both side of chemical reaction. These ions are cancel out. Their presence can not effect the equilibrium of reaction that's why these ions are omitted in net ionic equation.
