They determined that (1) An atom is mostly empty space with a sense, positively charged nucleus, because most particles passed straight through the gold foil, but occasionally they would deflect, sometimes by a very large margin
<em>Answer:</em>
<em>Chemical equations must be balanced to satisfy the law of conservation of matter, that states that matter cannot be produced or destroyed in a closed system. The law of conservation of mass governs the balancing of a chemical equation.</em>
Explanation:
Answer:
Density = 11.4 g/cm³
Explanation:
Given data:
Density of lead = ?
Height of lead bar = 0.500 cm
Width of lead bar = 1.55 cm
Length of lead bar = 25.00 cm
Mass of lead bar = 220.9 g
Solution:
Density = mass/ volume
Volume of bar = length × width × height
Volume of bar = 25.00 cm × 1.55 cm × 0.500 cm
Volume of bar = 19.4 cm³
Density of bar:
Density = 220.9 g/ 19.4 cm³
Density = 11.4 g/cm³
Answer:
A new substance was forming
Explanation:
Two types of changes are undergone by substances involved in a reaction. They are physical changes and chemical changes. Physical changes are those changes that does not involve the synthesis of a new product. On the other hand, CHEMICAL CHANGES alters the chemical composition of the substances involved, and hence, new substances are formed.
Chemical changes are usually characterized by change of temperature, color change, evolution of a gas etc. According to this question, Mia mixed two substances in a test tube and noticed that the test tube became warm. She also noticed gas coming from the test tube. Based on Mia's observations, a CHEMICAL CHANGE, LEADING TO THE FORMATION OF NEW SUBSTANCE, HAS OCCURRED.
Given :
A 10.99 g sample of NaBr contains 22.34% Na by mass.
To Find :
How many grams of sodium does a 9.77g sample of sodium bromine contain.
Solution :
By law of constant composition , in any given chemical compound, the elements always combine in the same proportion with each other.
Therefore , percentage of Na by mass in NaBr will be same for every amount .
Percentage of Na in 9.77 g NaBr is 22.34 % too .
Gram of Na = 
.
Hence , this is the required solution .
