diff --git a/go/05-concurrency/deadlock.go b/go/05-concurrency/deadlock.go
new file mode 100644
index 0000000..931c201
--- /dev/null
+++ b/go/05-concurrency/deadlock.go
@@ -0,0 +1,17 @@
+package main
+
+func print(ci <-chan int) {
+	//TODO: implement
+}
+
+func main() {
+
+	c := make(chan int)
+
+	c <- 1
+	c <- 2
+	c <- 3
+	close(c)
+
+	print(c)
+}
diff --git a/go/05-concurrency/mergeSort.go b/go/05-concurrency/mergeSort.go
new file mode 100644
index 0000000..4160246
--- /dev/null
+++ b/go/05-concurrency/mergeSort.go
@@ -0,0 +1,86 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"sort"
+	"time"
+)
+
+func mergeSortSequential(data []float64) {
+	if len(data) <= 1 {
+		return
+	}
+
+	mid := len(data) / 2
+	left := data[:mid]
+	right := data[mid:]
+
+	mergeSortSequential(left)
+	mergeSortSequential(right)
+
+	copy(data, merge(left, right))
+}
+
+func merge(left, right []float64) []float64 {
+	result := make([]float64, 0, len(left)+len(right))
+	i, j := 0, 0
+
+	for i < len(left) && j < len(right) {
+		if left[i] < right[j] {
+			result = append(result, left[i])
+			i++
+		} else {
+			result = append(result, right[j])
+			j++
+		}
+	}
+
+	result = append(result, left[i:]...)
+	result = append(result, right[j:]...)
+
+	return result
+}
+
+func main() {
+
+	//1. DATA CREATION
+	data := make([]float64, 1000*1000*20)
+
+	for i := range data {
+		data[i] = rand.Float64() * 100 // Random floats between 0 and 100
+	}
+
+	expected := make([]float64, len(data))
+	copy(expected, data)
+	sort.Float64s(expected)
+
+	//2. SORTING
+	start := time.Now()
+
+	mergeSortSequential(data)
+
+	elapsed := time.Since(start)
+	fmt.Printf("MergeSort took %s\n", elapsed)
+
+	//3. VERIFICATION
+	if sort.Float64sAreSorted(data) {
+		fmt.Println("Data is sorted correctly")
+	} else {
+		fmt.Println("Data is NOT sorted correctly")
+	}
+
+	if len(data) != len(expected) {
+		fmt.Println("Data and expected slices have different lengths")
+		return
+	}
+
+	for i := range data {
+		if data[i] != expected[i] {
+			fmt.Println("Data and expected slices do not match")
+			return
+		}
+	}
+
+	fmt.Println("Data and expected slices match")
+}
diff --git a/go/05-concurrency/select.go b/go/05-concurrency/select.go
new file mode 100644
index 0000000..8af6e52
--- /dev/null
+++ b/go/05-concurrency/select.go
@@ -0,0 +1,19 @@
+package main
+
+import (
+	"math/rand"
+	"time"
+)
+
+func main() {
+
+	ch1 := make(chan string)
+
+	go func() {
+		time.Sleep(time.Duration(rand.Intn(5)+1) * time.Second)
+		ch1 <- "Message from channel 1"
+	}()
+
+	msg1 := <-ch1
+	println("Received:", msg1)
+}